San Rafael 94903 · Lucas Valley · APN 164-431-32 · Unincorporated Marin
Zoned R1-B-LV in Unincorporated Marin with likely ministerial ADU eligibility and mapped FEMA AE flood / CAL FIRE high fire hazard severity zone (local responsibility area) due diligence; benchmark value $1,556,000 ($1,369,000–$1,743,000).
Zone R1-B-LV allows residential use qualifying for ministerial ADU review under state law (1 ADU permit permitted within ¼ mile in 36 months).
Source: Unincorporated Marin zoning · CA Gov. Code 66314
Public building records show issued construction/renovation work on this parcel (8 total permits, latest Nov 19, 2024).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (parcel APN)
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)
Automated synthesis of indexed municipal, county, state, and federal public records — informational context only, not a formal appraisal, survey, or legal/tax determination.
Since November 2024 within ½ mile: 1 permitted, 1 proposed or in review; 1 demolition.
3 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.
140 permits within ½ mile since November 2024
$1,556,000
Benchmark range: $1,369,000 – $1,743,000
Located in a mapped Fire Hazard Severity Zone. Expect Chapter 7A ignition-resistant building standards, defensible-space inspections, and stricter property insurance underwriting.
Source: CAL FIRE FHSZ (map Mar 24, 2025)
Closest lead: New home (0.11 mi NE, 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)
Sale triggers reassessment to 1.00% base + ~0.15% voter debt (~$1,529/mo). Confirm exact Mello-Roos / CFD special assessments on the county tax bill.
Source: CA Const. Art. XIIIA (Prop 13) · County Tax Collector
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.
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Geography: permits located by parcel, ½ mile radius · Retrieved Nov 13, 2026
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.
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 13, 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-B-LV as single-family residential, checked against the zone description on Oct 24, 2026
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.
Permit issued and active for 7 yr (first record Nov 18, 2019), with no completion or new permit record in 7 yr. · $2,000 declared valuation
In "Applied" for 5.5 yr (since May 28, 2021), with no new permit record in 5.5 yr. · 1 unit · $110,000 declared valuation
In "Entitled" for 5.1 yr (since Sep 23, 2021), with no new permit record in 5.1 yr. · 1 unit
In "Entitled" for 3.8 yr (since Jan 14, 2023), with no new permit record in 3.8 yr. · 1 unit
In "Entitled" for 3.3 yr (since Jul 10, 2023), with no new permit record in 3.3 yr. · 1 unit
Permit issued and active for 3.2 yr (first record Aug 14, 2023), with no completion or new permit record in 3.2 yr. · 1 unit
Nearby roof replacement (1125 Idylberry Rd): First appeared in published agency feed
Record B49056 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Nearby other (55 Pikes Peak Dr): First appeared in published agency feed
Record B49039 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Nearby other (913 Appleberry Dr): First appeared in published agency feed
Record B49034 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Nearby roof replacement (1 Mt Palomar Ct): First appeared in published agency feed
Record B48964 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Nearby remodel / interior alteration (1129 Idylberry Rd): First appeared in published agency feed
Record 94620 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Nearby other (125 Mt Lassen Dr): First appeared in published agency feed
Record B48900 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Nearby roof replacement (3 Mt Darwin Ct): First appeared in published agency feed
Record B48883 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Latest published Zillow Home Value Index (ZHVI) update
Changed from $1,200,587 in September 2025 to $1,250,063 in September 2026.
Source: Zillow Home Value Index (ZHVI) · Data provided by Zillow · Geography: ZIP 94903 (not a parcel appraisal)
90 Mt Lassen Dr · $400 valuation
Records span Dec 8, 2025 to Jan 8, 2026 (1 permit).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) & HCD APR (grouped project within ½ mile)
125 Mt Lassen Dr (Adu 125a) · 1 unit · $56,500 valuation
Records span Dec 11, 2024 to Nov 19, 2025 (1 permit).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) & HCD APR (grouped project within ½ mile)
Annual ZIP 94903 home-value index checkpoint
Changed from $1,237,445 in September 2024 to $1,200,587 in September 2025.
Source: Zillow Home Value Index (ZHVI) · Data provided by Zillow · Geography: ZIP 94903 (not a parcel appraisal)
1 unit
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) & HCD APR (grouped project within ½ mile)
Other permit application filed (B40230)
Current status: Issued
SFD - C/O like for like boiler in exterior closet — Replace Mechanical Appliance · Declared valuation: $13,000 · Contractor: John Owens Services Inc
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Geography: parcel
Other permit issued (B40230)
Recorded status: Issued
SFD - C/O like for like boiler in exterior closet — Replace Mechanical Appliance · Declared valuation: $13,000 · Contractor: John Owens Services Inc
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Geography: parcel
Annual ZIP 94903 home-value index checkpoint
Changed from $1,210,123 in September 2023 to $1,237,445 in September 2024.
Source: Zillow Home Value Index (ZHVI) · Data provided by Zillow · Geography: ZIP 94903 (not a parcel appraisal)
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 →In "Entitled" for 2.9 yr (since Dec 7, 2023), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121).
In "Entitled" for 3.3 yr (since Jul 10, 2023), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121).
In "Entitled" for 3.8 yr (since Jan 14, 2023), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121).
In "Entitled" for 5.1 yr (since Sep 23, 2021), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121).
In "Applied" for 5.5 yr (since May 28, 2021), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121).
Active in "Issued" for 3.2 yr (first record Aug 14, 2023) with no new permit activity recorded in 3.2 yr.
Substantial improvements (additions, interior remodels, ADUs, commercial TI, and new builds) across 768 parcels
Small prior baseline
City baseline: 16.4 / 1k
10 in trailing 24m
Includes 3 ADUs
| Builder / contractor | Primary specialty | Here / ½ mi | ½ mi valuation | Citywide 24m trend |
|---|---|---|---|---|
| Owner Builder | Remodel / interior alteration | 1 on parcel24 in ½ mi | $2,746,400 | 226 vs 240 prior−6% |
| Vida Building | Addition (adds square footage) | 1 on parcel1 in ½ mi | $230,000 | 3 vs 2 prior |
| Abril Roofing | Roof replacement | 1 on parcel1 in ½ mi | $25,300 |
| Permit category | Sample (n) | 25th pct | Median (50th) | 75th pct | 90th pct | Recent 24m median |
|---|---|---|---|---|---|---|
| New single-family home | 121 | 166d | 253d | 456d | 686d | 211d(vs 273d 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) |
HUD Small Area Fair Market Rent · ZIP 94903
HUD FY 2026 · 40th-percentile gross rentCensus ACS 5-year median gross rent (all bedroom counts combined):
Area home-value benchmarks (not an appraisal)
ZIP & neighborhood mediansUnder 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 ($15,550/yr) + local voter-approved bond debt ($2,333/yr) + fixed direct levies/Mello-Roos ($450/yr).
Mapped hazard zone insurance context on this parcel:
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.
−$77,210/yr
Cash needed: $342,100
NOI: $17,145/yr
P&I: $7,863/mo
For $0/mo net cash flow
At $4,175/mo gross rent
| 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 | $3,841/mo | −$6,914/mo | -24.3% | $13,492/mo | −$6,896/mo |
| Base (your inputs) | Your entered assumptions, 3.0%/yr rent growth | $4,175/mo | −$6,434/mo | -22.6% | $12,488/mo | −$6,180/mo |
| Optimistic (cap-limited) | +6% starting rent, 3% vacancy, 4.5%/yr rent growth (capped by AB 1482 ceiling of 8.6%/yr) | $4,426/mo | −$6,158/mo | -21.6% | $12,198/mo | −$5,635/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.
SFD - C/O like for like boiler in exterior closet — Replace Mechanical Appliance
Pool Repairs
Upgrade main panel to California 320 amps, provide new circuits for new steam unit, sauna, hot tub and pool — Service Upgrade
Remod, Addtn, Convrsn
Window replacement in kind (1) — Non-structural Door/Window Replacement
polyurethane foam over tar and gravel no tear off — ReRoofing
Installing new mini split system — Mechanical Appliance
Upgrade Main Service Panel at original location. (Original unsafe 100A underground Zinsco replaced with 125A Eaton underground equipment.) Upgrade grounding and bonding systems to current code. Replace interior Zinsco sub panel with Eaton sub panel at hallway near kitchen. — Service Upgrade
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Geography: parcel (APN) · Retrieved Nov 13, 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.
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.
Source: County of Marin GIS (MarinMap), Zoning (11 cities and unincorporated Marin) · Geography: zoning district polygon at parcel point · Retrieved Nov 13, 2026
0.28 acres
Assessor's classification for assessment purposes. This is not zoning.
1 MT DARWIN CT
Source: County of Marin GIS (MarinMap), Parcels · Geography: parcel · Retrieved Nov 13, 2026
Search by parcel number 164-431-32. Assessed value is not market value.
Search by parcel number 164-431-32 (Marin County Tax Collector)
Permits issued in unincorporated Marin in the past 48 months. Each city keeps its own records.
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.
| 0 vs 0 prior |
| Electrical Assistance | Plumbing / water heater / sewer | 1 on parcel1 in ½ mi | $16,000 | 0 vs 0 prior |
| John Owens Services | Other | 1 on parcel1 in ½ mi | $13,000 | 0 vs 0 prior |
| Bellows Plumbing Heating And Air | HVAC / heat pump | 1 on parcel1 in ½ mi | $7,500 | 0 vs 0 prior |
| Divine Electric | Electrical / panel | 1 on parcel1 in ½ mi | $6,500 | 2 vs 1 prior |
| Jemico | Windows / doors / siding | 1 on parcel1 in ½ mi | $4,494 | 0 vs 0 prior |
| Tim Lawlor Construction Recent nearby: 25 Mt Lassen Dr (Jul 24, 2024) | Remodel / interior alteration | 5 in ½ mi | $485,000 | 0 vs 1 prior |
| Loic Humbert Recent nearby: 7 Mt Lassen Dr #A (Sep 20, 2016) | Remodel / interior alteration | 4 in ½ mi | $98,000 | 0 vs 0 prior |
| 316 |
| 103d |
| 160d |
| 249d |
| 440d |
| 157d(vs 167d 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) |
| Roof replacementOn this parcel | 3,663 | 0d | 0d | 0d | 0d | 0d |
| HVAC / heat pumpOn this parcel | 2,946 | 0d | 0d | 0d | 0d | 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.