55 Berens Dr

Kentfield 94904 · Kentfield · APN 074-122-08 · Unincorporated Marin

Compare Property brief (PDF)Timeline ↓Calculator ↓Official records ↓

Executive Verdict · Public-Records Synthesis

Flood:FEMA AE ADU screen:Likely eligible Benchmark est.:$2,274,000 Yr 1 Prop 13 est.:$2,217/mo

Zoned R1-B1 in Unincorporated Marin with likely ministerial ADU eligibility and mapped FEMA AE flood due diligence; benchmark value $2,274,000 ($2,001,000–$2,547,000).

Upsides & Opportunities

Ministerial ADU / JADU pathway likely eligibleDetails ↓
Zone R1-B1 allows residential use qualifying for ministerial ADU review under state law (4 ADU permits permitted within ¼ mile in 36 months).
Source: Unincorporated Marin zoning · CA Gov. Code 66314
Documented permitted upgrades (+$11,763 contributory est.)Details ↓
Public building records show issued construction/renovation work on this parcel (1 total permit, latest Oct 1, 2025).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (parcel APN)
Above-average reinvestment in KentfieldDetails ↓
103 substantial renovation & housing permits over 24 months (40.9 per 1,000 parcels vs. 16.3 citywide baseline) (#7 of 22 neighborhoods).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (Kentfield)

Watchouts & Due Diligence

FEMA Special Flood Hazard Area (AE, about 4% of the lot of lot)Details ↓
Zone AE: 1% annual chance flood (Special Flood Hazard Area) overlaps this parcel. Expect mandatory flood insurance for federally backed loans and floodplain elevation/mitigation rules for new units or SB 9 applications.
Source: FEMA National Flood Hazard Layer (parcel polygon)
6 slow or stalled nearby projects within ½ mileDetails ↓
Closest lead: Magnolia Village (0.2 mi S, entitled). Inspect timeline history before assuming near-term completion.
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · HCD APR (½-mile radius)
Year 1 Prop 13 tax reset (~$26,601/yr at $2,274,000)Details ↓
Sale triggers reassessment to 1.00% base + ~0.15% voter debt (~$2,217/mo). Confirm exact Mello-Roos / CFD special assessments on the county tax bill.
Source: CA Const. Art. XIIIA (Prop 13) · County Tax Collector

Automated synthesis of indexed municipal, county, state, and federal public records — informational context only, not a formal appraisal, survey, or legal/tax determination.

What's changing nearby

Since November 2024 within ½ mile: 11 permitted; 1 demolition; 1 commercial or mixed-use project.

13 projects with a record in this window, grouped by us from permits and State housing reports. Units are as proposed on each project's latest record and counted at its current stage.

234 permits within ½ mile since November 2024

New construction5
Adds housing (ADU)7 · 7 units
Demolition1
Additions & renovations21
Building systems151
Repairs10
Other39

The map shows new construction, ADUs, demolitions, additions, and renovations. Routine systems work (roofs, HVAC, water heaters) is counted but not mapped. Unit counts are as stated on permits.

Explore projects on the map →Explore sales & prices →

Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Geography: permits located by parcel, ½ mile radius · Retrieved Nov 15, 2026

Estimated price, listing status & sales records

Benchmark valuation & transaction history

Estimated PriceZHVI + ACS + Permits

$2,274,000

Benchmark range: $2,001,000 – $2,547,000

Listing StatusOff Market

Not currently listed for sale

Compare nearby sales & prices on map →

Last Sold & Tax Roll

No deed price in open GIS feed

Verify on Assessor's property search

How this estimated price is calculated (ZIP ZHVI + Neighborhood ACS + Permit Model)

Model monthly ownership cost ↓

1. Area home value baseline: 70% ZIP 94904 Zillow ZHVI ($2,308,409, September 2026) + 30% Kentfield ACS median ($2,000,000); $2,215,886
2. Parcel & lot adjustment (1.02×): Single-family lot (7,797 sq ft, +2.1% lot-size adjustment vs 6,000 sq ft standard lot); +$46,441
3. Documented permitted improvements: +$11,763 from documented permits (1 pool/solar upgrade); +$11,763

Public-records benchmark estimate combining Zillow Home Value Index (Data provided by Zillow), Census ACS 5-year estimates, parcel land-use/lot characteristics, and issued building permits. Not an official appraisal.

What could be built here

A screen, not a determination

ADU or junior ADU

Likely eligible

Zoned R1-B1 (single-family residential): state law allows ADUs where homes are allowed.

What we couldn't check (4)

Setbacks, height and size limits in the local ADU ordinance
Utility and sewer capacity, fire access
Historic district or landmark status: we have no historic layer for this area yet.
Locally adopted fire hazard maps, which can be broader than the State's.

SB 9: two homes on the lot

Possible, with conditions

Zoned R1-B1, a single-family residential zone.
FEMA Special Flood Hazard Area (Zone AE) covers about 4% of the lot: the project must meet the National Flood Insurance Program floodplain standards, or the lot needs a map revision.

What we couldn't check (6)

Whether a tenant lived there in the last 3 years, or the building was withdrawn from rent under the Ellis Act
Rent-controlled or deed-restricted affordable housing on the lot
Wetlands, habitat, farmland, hazardous waste sites and conservation easements
Local SB 9 standards (size, setbacks, parking)
Historic district or landmark status: we have no historic layer for this area yet.
Locally adopted fire hazard maps, which can be broader than the State's.

SB 9: split into two lots

Possible, with conditions

Zoned R1-B1, a single-family residential zone.
The lot is 7,797 sq ft by the assessor, room for two lots of at least 1,200 sq ft, each at least 40% of the original.
FEMA Special Flood Hazard Area (Zone AE) covers about 4% of the lot: the project must meet the National Flood Insurance Program floodplain standards, or the lot needs a map revision.

What we couldn't check (6)

Owner-occupancy: the applicant must sign an affidavit to live in one of the homes for 3 years
Whether the lot was created by an earlier SB 9 split, or the owner split an adjacent lot
Whether a tenant lived there in the last 3 years, or the building was withdrawn from rent under the Ellis Act
Wetlands, habitat, farmland, hazardous waste sites and conservation easements
Historic district or landmark status: we have no historic layer for this area yet.
Locally adopted fire hazard maps, which can be broader than the State's.

Mapped hazards on this lot

Fire hazard severity zone: Not in a State-mapped zone
FEMA flood zone: Zone X: 0.2% annual chance flood hazard (shaded X), about 83% of the lotZone X: 0.2% annual chance flood hazard (shaded X), about 9% of the lotZone AE: 1% annual chance flood (Special Flood Hazard Area), about 4% of the lotZone AE: 1% annual chance flood (Special Flood Hazard Area), about 4% of the lotFIRM panel 06041C0458F, effective March 16, 2016. Official flood map
Earthquake fault zone: Not in an Alquist-Priolo Earthquake Fault Zone

Built nearby: within ¼ mile since November 2023

Accessory dwelling unit (new or conversion)4

See them on the map →

Permit counts, by the date issued (or applied, if not yet issued). Lot splits are planning cases, which we don't have.

We read public zoning and hazard maps against state law (ADUs: Gov. Code 66314; SB 9: Gov. Code 65852.21 and 66411.7). Local rules, title, tenancy history and site conditions can change the answer. Check with Unincorporated Marin's planning department before relying on it.

Sources: County of Marin GIS (MarinMap), Zoning (11 cities and unincorporated Marin) (retrieved Nov 15, 2026) · CAL FIRE Office of the State Fire Marshal, Fire Hazard Severity Zones in the State Responsibility Area (effective 2024-04-01) (retrieved Nov 9, 2026) · CAL FIRE Office of the State Fire Marshal, Fire Hazard Severity Zones in the Local Responsibility Area (map dated 2025-03-24) (retrieved Nov 9, 2026) · FEMA, National Flood Hazard Layer — flood hazard zones (retrieved Nov 9, 2026) · FEMA, National Flood Hazard Layer — FIRM panels (retrieved Nov 9, 2026) · California Geological Survey, Alquist-Priolo Earthquake Fault Zones (retrieved Nov 9, 2026) · Zoning classes: our classification of R1-B1 as single-family residential, checked against the zone description on Oct 24, 2026

Property & area intelligence timeline

65 events · 36 slow/stalled projects

Chronological history of building permit applications and issuances, snapshot-dated status changes, State housing entitlements, surrounding development within ½ mile, and area home-value trends.

Slow-moving or stalled projects (36)

Active projects spending 12+ months pre-issuance, 24+ months under construction, or 6+ months without new records

StalledNew home at 617 College AveIssued
0.38 mi W
Permit issued and active for 13 yr (first record Nov 12, 2013), with no completion or new permit record in 12.7 yr. · 1 unit · $1,000,000 declared valuation
StalledNew home at 1 Fay DrIssued
0.46 mi NE
Permit issued and active for 13 yr (first record Oct 28, 2013), with no completion or new permit record in 12.5 yr. · 1 unit · $380,508 declared valuation
StalledNew commercial building at 675 Sir Francis Drake BlvdIssued
0.39 mi NE
Permit issued and active for 12.7 yr (first record Mar 6, 2014), with no completion or new permit record in 12.5 yr. · $2,400,000 declared valuation
StalledDemolition at 101 Goodhill RdIssued
0.48 mi W
Permit issued and active for 12.4 yr (first record Jun 9, 2014), with no completion or new permit record in 12.4 yr. · $5,000 declared valuation
StalledDemolition at 112 Ter AveApplied
0.46 mi N
In "Applied" for 12.4 yr (since Jun 18, 2014), with no new permit record in 12.4 yr. · $19,805 declared valuation
StalledDemolition at 43 Mcallister AveIssued
0.2 mi NE
Permit issued and active for 11.9 yr (first record Dec 8, 2014), with no completion or new permit record in 11.7 yr. · $1,000 declared valuation

202610 events

Oct 26, 2026 – Nov 9, 2026Snapshot windowNearby snapshot change
0.49 mi SE
Nearby permit (caed30fe5602515ed7bb1aafc27cf14c28c27608): First appeared in published agency feed
Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Oct 26, 2026 – Nov 9, 2026Snapshot windowNearby snapshot change
0.49 mi SE
Nearby permit (fba95eb030ed7d34532e4acacd38c98e5960d7a6): First appeared in published agency feed
Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Nov 4, 2026 – Nov 5, 2026Snapshot windowNearby snapshot change
0.48 mi SW
Nearby other (1 Fern Rd): First appeared in published agency feed
Record B49004 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Oct 28, 2026 – Oct 29, 2026Snapshot windowNearby snapshot change
470 ft N
Nearby other (70 Lancaster Ave): First appeared in published agency feed
Record B48941 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Oct 28, 2026 – Oct 29, 2026Snapshot windowNearby snapshot change
0.41 mi E
Nearby commercial tenant improvement (250 Bon Air Rd): First appeared in published agency feed
Record 94609 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Oct 27, 2026 – Oct 28, 2026Snapshot windowNearby snapshot change
0.5 mi N
Nearby roof replacement (136 Terrace Ave): First appeared in published agency feed
Record B48914 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Oct 23, 2026 – Oct 23, 2026Snapshot windowNearby snapshot change
0.49 mi SE
Nearby permit (b8db6838c020c1df3849679810d5f2210e644e76): First appeared in published agency feed
Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Oct 23, 2026 – Oct 23, 2026Snapshot windowNearby snapshot change
0.49 mi SE
Nearby permit (d167602d8a61a9dbcae8bb0646178d41cefc3920): First appeared in published agency feed
Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
September 2026Market trend
ZIP 94904
ZIP 94904 typical home value: $2,308,409 (+7.0% year-over-year)
Latest published Zillow Home Value Index (ZHVI) update
Changed from $2,157,052 in September 2025 to $2,308,409 in September 2026.
Source: Zillow Home Value Index (ZHVI) · Data provided by Zillow · Geography: ZIP 94904 (not a parcel appraisal)
Sep 30, 2026Nearby project · Issued
0.34 mi N
Accessory dwelling unit at 847 Sir Francis Drake Blvd — Issued
847 Sir Francis Drake Blvd · 1 unit · $240,000 valuation
Records span Mar 12, 2026 to Sep 30, 2026 (1 permit).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) & HCD APR (grouped project within ½ mile)

20255 events

Dec 19, 2025Nearby project · Applied
0.44 mi NW
Demolition at 801 College Ave — Applied
801 College Ave · $75,000 valuation
⏱ Slow turnaround:In "Applied" for 11 mo (since Dec 19, 2025), with no new permit record in 11 mo.
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) & HCD APR (grouped project within ½ mile)
Nov 26, 2025Nearby project · Issued
440 ft N
Accessory dwelling unit at 70 Berens Dr (a D U 70 A) — Issued
70 Berens Dr (A D U 70 A) · 1 unit · $200,000 valuation
Records span Jul 18, 2025 to Nov 26, 2025 (1 permit).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) & HCD APR (grouped project within ½ mile)
Oct 1, 2025Permit applied
On this parcel
Solar / battery storage permit application filed (B44159)
Current status: Issued
install 7.06KW (17) Roof Mtd PV; (8) MCI-2; (1) PW3 = 13.5kwh. · Declared valuation: $27,230 · Contractor: Cobalt Power Systems Inc
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Geography: parcel
Oct 1, 2025Permit issued
On this parcel
Solar / battery storage permit issued (B44159)
Recorded status: Issued
install 7.06KW (17) Roof Mtd PV; (8) MCI-2; (1) PW3 = 13.5kwh. · Declared valuation: $27,230 · Contractor: Cobalt Power Systems Inc
Turnaround:Issued same day as application
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Geography: parcel
September 2025Market trend
ZIP 94904
ZIP 94904 typical home value: $2,157,052 (−4.4% year-over-year)
Annual ZIP 94904 home-value index checkpoint
Changed from $2,256,428 in September 2024 to $2,157,052 in September 2025.
Source: Zillow Home Value Index (ZHVI) · Data provided by Zillow · Geography: ZIP 94904 (not a parcel appraisal)

Showing 15 of 65 timeline events

Recorded sales & deed transfers: California county recorders do not publish open bulk deed-transfer feeds without owner-PII restrictions, so individual sale deeds are not redistributed here. For official assessment roll and recorded transfer history in Unincorporated Marin, inspect Assessor's property search ↗.

Development graph & closer investigation

6 investigation leads · 10 active builders

Cross-referenced intelligence from our historical development graph—connecting parcels, permits, entity-resolved builders, empirical review-time distributions, and neighborhood renovation trends.

Explore full Unincorporated Marin development graph →

Developments deserving closer investigation (6)

On this parcel & within ½ mile

Magnolia VillageEntitled>90th pct review time (3.8 yr)20 units
0.2 mi S
In "Entitled" for 3.8 yr (since Feb 1, 2023), exceeding the 292d median and 313d 90th percentile for new multifamily / condos / mixed-use permits in Unincorporated Marin (n=21). High-impact scale (20 housing units, 4 deed-restricted affordable across 0 permits).
New home at 617 College AveIssuedNo new record in 12.7 yr$1,000,000
0.38 mi W
Active in "Issued" for 13 yr (first record Nov 12, 2013) with no new permit activity recorded in 12.7 yr. High-impact scale (1 housing unit, $1,000,000 declared valuation across 1 permit).
Accessory dwelling unit at 625 College Ave (a D U 627)IssuedNo new record in 3 yr$4,500,000
0.38 mi W
Active in "Issued" for 3.9 yr (first record Dec 7, 2022) with no new permit activity recorded in 3 yr. High-impact scale (1 housing unit, $4,500,000 declared valuation across 1 permit).
New commercial building at 675 Sir Francis Drake BlvdIssuedNo new record in 12.5 yr$2,400,000
0.39 mi NE
Active in "Issued" for 12.7 yr (first record Mar 6, 2014) with no new permit activity recorded in 12.5 yr. High-impact scale ($2,400,000 declared valuation across 2 permits).
New home at 105 Oak AveIssuedNo new record in 14 mo$965,000
0.47 mi N
Active in "Issued" for 4.3 yr (first record Jul 15, 2022) with no new permit activity recorded in 14 mo. High-impact scale (1 housing unit, $965,000 declared valuation across 3 permits).
Accessory dwelling unit at 30 Berens DrApplied>90th pct review time (5.1 yr)
450 ft NE
In "Applied" for 5.1 yr (since Oct 11, 2021), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121).

Neighborhood renovation & housing momentum: Kentfield

Substantial improvements (additions, interior remodels, ADUs, commercial TI, and new builds) across 2,518 parcels

Rank #7 of 22 neighborhoods in acceleration

Last 12m vs prior 12m: 41 vs 62 permits
24m rate per 1,000 parcels: 40.9
5-year substantial permits: 332
Housing additions (24m): 36 units

Active builders & contractors connected to this area (10)

Entity-resolved across corporate suffixes (INC / LLC / CORP)

Builder / contractor	Primary specialty	Here / ½ mi	½ mi valuation	Citywide 24m trend
Cobalt Power	Solar / battery storage	1 on parcel1 in ½ mi	$27,230	0 vs 0 prior
Owner Builder Recent nearby: 847 Sir Francis Drake Blvd (Sep 30, 2026)	Remodel / interior alteration	45 in ½ mi	$7,444,600	226 vs 239 prior−5%
Owner Recent nearby: 38 Berens Dr (Jul 3, 2025)	Remodel / interior alteration	31 in ½ mi	$2,102,208	25 vs 15 prior+67%
Mccarthy Building Recent nearby: 250 Bon Air Rd Bldg G (Jun 6, 2017)	New commercial / non-residential building	9 in ½ mi	$161,760	0 vs 0 prior
Tembrock Ingrassia Builders Recent nearby: 101 Goodhill Rd (May 6, 2021)	New garage / accessory structure	5 in ½ mi	$1,380,000	0 vs 0 prior
Hendrickson Pools Recent nearby: 112 Mcallister Ave (Jan 4, 2024)	Pool / spa	5 in ½ mi	$805,000	3 vs 4 prior
Levine Design And Construction Recent nearby: 82 Berens Dr (Apr 9, 2018)	Addition (adds square footage)	5 in ½ mi	$779,000	1 vs 4 prior
Michael Stone Recent nearby: 33 Rosebank Ave (Apr 20, 2023)	Remodel / interior alteration	5 in ½ mi	$417,600	2 vs 1 prior
Goltermann Construction Recent nearby: 6 Fay Dr (Nov 29, 2016)	Addition (adds square footage)	4 in ½ mi	$691,500	0 vs 0 prior
Bay City Contractors Recent nearby: 20 Rosebank Ave (Aka 20a Rosebank) (Apr 11, 2024)	Remodel / interior alteration	4 in ½ mi	$127,500	0 vs 2 prior

How long projects typically spend in review in Unincorporated Marin

Empirical turnaround from application to issuance (trailing 5 years)

Permit category	Sample (n)	25th pct	Median (50th)	75th pct	90th pct	Recent 24m median
New single-family home	121	166d	253d	456d	686d	210d(vs 276d prior)
New multifamily / condos / mixed-use	21	272d	292d	293d	313d	293d(vs 197d prior)
Accessory dwelling unit (new or conversion)	298	120d	204d	331d	549d	214d(vs 181d prior)
Addition (adds square footage)	316	103d	160d	249d	440d	159d(vs 166d prior)
Remodel / interior alteration	1,054	36d	83d	148d	266d	112d(vs 77d prior)
Commercial tenant improvement	81	99d	148d	233d	443d	152d(vs 150d prior)
Solar / battery storageOn this parcel	2,977	0d	0d	0d	2d	0d

Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Computed from issued permits with recorded application and issuance dates over the trailing 60 months. Categories with fewer than 20 permits are excluded.

Ownership & rental scenario calculator

Prop 13, ADU pro forma & area benchmarks

Area rent & home-value benchmarks (kept separate from your assumptions)

Click any benchmark to pre-fill the calculator

HUD Small Area Fair Market Rent · ZIP 94904

HUD FY 2026 · 40th-percentile gross rent

Census ACS 5-year median gross rent (all bedroom counts combined):

Kentfield$2,832±$294

ZIP 94904$2,712±$122

Area home-value benchmarks (not an appraisal)

ZIP & neighborhood medians

Zillow ZHVI · ZIP 94904(as of September 2026)Data provided by Zillow · typical mid-tier home value in ZIP

$2,308,409

ACS Median Home Value · KentfieldCensus ACS 2020–2024 owner-occupied self-reported median

$2,000,000+

ACS Median Home Value · ZIP 94904Census ACS 2020–2024 owner-occupied self-reported median

$2,000,000+

1. Purchase, financing & Prop 13 tax reassessment

Purchase price ($)Down payment (%)$455,000Interest rate (%)Loan termClosing costs (%)$45,500

Prop 13 post-purchase property tax estimate

$2,528/mo ($30,333/yr · 1.17%)

Under California Proposition 13, the seller's historical assessed value does not carry over to a buyer. On sale, the parcel is reassessed at the purchase price: 1.00% base rate ($25,985/yr) + local voter-approved bond debt ($3,898/yr) + fixed direct levies/Mello-Roos ($450/yr).

Voter bond rate (%)$3,898/yrDirect levies / Mello-Roos ($/yr)Check Assessor's property search ↗

2. Your rent & operating assumptions

Monthly gross rent ($)Your assumptionVacancy allowance (%)−$299/moManagement (%)$454/moMaintenance (%)$299/moCapEx reserve (%)$299/moInsurance ($/mo)$3,300/yrHOA dues ($/mo)Owner utilities ($/mo)

Mapped hazard zone insurance context on this parcel:

Parcel intersects a FEMA Special Flood Hazard Area (Zone AE: 1% annual chance flood (Special Flood Hazard Area)). Federally backed mortgages require flood insurance in SFHA zones.
Parcel intersects a FEMA Special Flood Hazard Area (Zone AE: 1% annual chance flood (Special Flood Hazard Area)). Federally backed mortgages require flood insurance in SFHA zones.

ADU / JADU Value-Add Pro Forma

Gov. Code § 66314: Likely eligible· 4 ADUs permitted within ¼ mi (36m)

Model adding a backyard ADU or garage conversion under California's Prop 13 blended new-construction assessment (existing house & land tax base stays intact; only ADU build cost is assessed) and SB 13 impact-fee rules.

Quick ADU presets:

HUD FMR benchmarks:

ADU size (sq ft)<750 sf: SB 13 fee-exemptBuild cost ($/sq ft)Hard/soft: $315,000Permits & fees ($)Total build: $323,500ADU cash (%)Cash: $80,875ADU loan rate (%)Loan: $242,625ADU term (yrs)P&I: $1,918/moADU rent ($/mo)NOI: +$1,735/mo

All-in ADU build cost

$323,500

Combined basis: $2,598,500

Standalone ADU yield on cost

6.44%

+$20,817/yr ADU NOI

ADU net cash-flow lift

−$183/mo

−$11,461 → −$11,644/mo total

Blended cap rate lift

0.02% → 0.82%

CoC: -27.5% → -24.0%

Supplemental Prop 13 tax

+$310/mo

+$3,720/yr on ADU cost only

Statutory notes: Under CA Gov. Code § 66324 (SB 13), local agencies cannot impose development impact fees on ADUs under 750 sq ft (plan-check, school district fees ≥500 sq ft, and utility connection fees still apply). Under CA Rev. & Tax. Code § 71, building an ADU triggers a supplemental assessment on the new construction value without reassessing the existing dwelling or land. Newly built ADUs also carry a rolling 15-year exemption from statewide AB 1482 rent caps from certificate of occupancy.

3. Scenario results (based on your assumptions)

Net monthly cash flow: −$11,644
Cash-on-cash return: -24.0%
Cap rate (Year 1 NOI): 0.82%
DSCR (NOI / debt): 0.13x
Break-even gross rent: $21,019/mo
Break-even vacancy: 0% (negative at full occ.)

Monthly cash-flow breakdown (Effective gross $5,676 − Operating $3,899 − Debt $13,421)

Gross scheduled rent$5,975

Vacancy allowance (5%)−$299

Effective gross income$5,676

Prop 13 property tax (1.17%)−$2,528

Property insurance−$320

Management (8%), maintenance (5%) & CapEx (5%)−$1,052

Net Operating Income (NOI)+$1,777

Mortgage principal & interest (2,062,625 loan)−$13,421

Net monthly cash flow−$11,644

4. Sensitivity & rent-stabilization ceiling (Unincorporated Marin)

Scenario	Assumptions	Year 1 Rent	Year 1 Cash Flow	Cash-on-Cash	Break-Even Rent	Year 5 Cash Flow
Conservative	−8% starting rent, +3% vacancy, +3% combined maintenance/CapEx, 1.5%/yr rent growth	$5,497/mo	−$12,331/mo	-25.5%	$22,709/mo	−$12,323/mo
Base (your inputs)	Your entered assumptions, 3.0%/yr rent growth	$5,975/mo	−$11,644/mo	-24.0%	$21,019/mo	−$11,298/mo
Optimistic (cap-limited)	+6% starting rent, 3% vacancy, 4.5%/yr rent growth (capped by AB 1482 ceiling of 8.6%/yr)	$6,334/mo	−$11,250/mo	-23.2%	$20,531/mo	−$10,518/mo

Rental regulatory context (informational only — not legal advice):

California AB 1482 (Tenant Protection Act, Civ. Code § 1947.12) caps annual rent increases at 5% + local CPI (max 10%) on covered properties.

Common statutory exemption signals under AB 1482

Housing issued a certificate of occupancy within the last 15 years (rolling exemption under AB 1482).
Separately alienable single-family homes or condominiums not owned by a corporation, REIT, or LLC with a corporate member (when required statutory notice is in the lease).
Owner-occupied duplexes where the owner occupied one unit from the start of the tenancy.

Permit history on this parcel

1 records

Solar / battery storageB44159
install 7.06KW (17) Roof Mtd PV; (8) MCI-2; (1) PW3 = 13.5kwh.
install 7.06KW (17) Roof Mtd PV; (8) MCI-2; (1) PW3 = 13.5kwh.
Applied
Oct 1, 2025
Issued
Oct 1, 2025
Recorded status
Issued as of Oct 1, 2025
Declared valuation
$27,230
Contractor:
Cobalt Power

Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Geography: parcel (APN) · Retrieved Nov 15, 2026 · Received and issued dates come from the County of Marin. The county publishes no final or expired status, so an issued permit stays 'Issued' after the work is done.

Housing activity reported to the State

No housing activity reported to the State for this parcel (2018–2025 reports).

Source: California HCD, Housing Element Annual Progress Report — Table A2 · Geography: project (parcel) · Retrieved Nov 9, 2026 · From Unincorporated Marin's Housing Element Annual Progress Reports. A project can appear in several report years as it moves from entitlement to permit to completion.

Zoning & planning

Zoning: R1-B1: Residential Single Family (Unincorporated Marin)

Source: County of Marin GIS (MarinMap), Zoning (11 cities and unincorporated Marin) · Geography: zoning district polygon at parcel point · Retrieved Nov 15, 2026

Parcel facts

Lot size: 7,797 sq ft
Assessor land use: Single-Resid. - Improved
Addresses on parcel: 1

Source: County of Marin GIS (MarinMap), Parcels · Geography: parcel · Retrieved Nov 15, 2026

Official records

Assessor's property search
Search by parcel number 074-122-08. Assessed value is not market value.
Property tax bill
Search by parcel number 074-122-08 (Marin County Tax Collector)
County permit lookup
Permits issued in unincorporated Marin in the past 48 months. Each city keeps its own records.
FEMA Flood Map Service Center
The official flood hazard map for this location. Our reading of it is under What could be built here.

This site does not show owner names.

Builder / contractor

Primary specialty

Here / ½ mi

½ mi valuation

Citywide 24m trend

Cobalt Power

Solar / battery storage

1 on parcel1 in ½ mi

$27,230

0 vs 0 prior

Owner Builder

Recent nearby: 847 Sir Francis Drake Blvd (Sep 30, 2026)

Remodel / interior alteration

45 in ½ mi

$7,444,600

226 vs 239 prior−5%

Owner

Recent nearby: 38 Berens Dr (Jul 3, 2025)

Remodel / interior alteration

31 in ½ mi

$2,102,208

25 vs 15 prior+67%

Mccarthy Building

Recent nearby: 250 Bon Air Rd Bldg G (Jun 6, 2017)

New commercial / non-residential building

9 in ½ mi

$161,760

0 vs 0 prior

Tembrock Ingrassia Builders

Recent nearby: 101 Goodhill Rd (May 6, 2021)

New garage / accessory structure

5 in ½ mi

$1,380,000

0 vs 0 prior

Hendrickson Pools

Recent nearby: 112 Mcallister Ave (Jan 4, 2024)

Pool / spa

5 in ½ mi

$805,000

3 vs 4 prior

Levine Design And Construction

Recent nearby: 82 Berens Dr (Apr 9, 2018)

Addition (adds square footage)

5 in ½ mi

$779,000

1 vs 4 prior

Michael Stone

Recent nearby: 33 Rosebank Ave (Apr 20, 2023)

Remodel / interior alteration

5 in ½ mi

$417,600

2 vs 1 prior

Goltermann Construction

Recent nearby: 6 Fay Dr (Nov 29, 2016)

Addition (adds square footage)

4 in ½ mi

$691,500

0 vs 0 prior

Bay City Contractors

Recent nearby: 20 Rosebank Ave (Aka 20a Rosebank) (Apr 11, 2024)

Remodel / interior alteration

4 in ½ mi

$127,500

0 vs 2 prior

Permit category

Sample (n)

25th pct

Median (50th)

75th pct

90th pct

Recent 24m median

New single-family home

121

166d

253d

456d

686d

210d(vs 276d prior)

New multifamily / condos / mixed-use

272d

292d

293d

313d

293d(vs 197d prior)

Accessory dwelling unit (new or conversion)

298

120d

204d

331d

549d

214d(vs 181d prior)

Addition (adds square footage)

316

103d

160d

249d

440d

159d(vs 166d prior)

Remodel / interior alteration

1,054

36d

83d

148d

266d

112d(vs 77d prior)

Commercial tenant improvement

99d

148d

233d

443d

152d(vs 150d prior)

Solar / battery storageOn this parcel

2,977

Scenario

Assumptions

Year 1 Rent

Year 1 Cash Flow

Cash-on-Cash

Break-Even Rent

Year 5 Cash Flow

Conservative

−8% starting rent, +3% vacancy, +3% combined maintenance/CapEx, 1.5%/yr rent growth

$5,497/mo

−$12,331/mo

-25.5%

$22,709/mo

−$12,323/mo

Base (your inputs)

Your entered assumptions, 3.0%/yr rent growth

$5,975/mo

−$11,644/mo

-24.0%

$21,019/mo

−$11,298/mo

Optimistic (cap-limited)

+6% starting rent, 3% vacancy, 4.5%/yr rent growth (capped by AB 1482 ceiling of 8.6%/yr)

$6,334/mo

−$11,250/mo

-23.2%

$20,531/mo

−$10,518/mo