San Rafael 94901 · California Park · APN 018-131-10 · Unincorporated Marin
Zoned R1-B3 in Unincorporated Marin with likely ADU & SB 9 infill eligibility and zero mapped flood, fire, or fault hazard overlaps; benchmark value $1,497,000 ($1,317,000–$1,677,000).
Zoned R1-B3 supports ministerial ADU/JADU review plus SB 9 both two-unit development and ministerial urban lot split on a 23,130 sq ft lot. Local precedent is active with 4 ADU permits within ¼ mile over the last 36 months.
Source: Unincorporated Marin zoning · CA Gov. Code 66314 & 65852.21
On-parcel permit history is indexed through Dec 7, 2022, letting you verify roof, HVAC, electrical, or structural work against seller disclosures.
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (parcel APN)
all of the lot of the parcel intersects Zone X: minimal flood hazard. Outside mandatory federal SFHA insurance rules, but check local drainage and finished-floor requirements.
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.
$1,497,000
Benchmark range: $1,317,000 – $1,677,000
Closest lead: 79 new homes at 0 Auburn St & Woodland Ave (0.36 mi N, applied). 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 (~$1,472/mo). Confirm exact Mello-Roos / CFD special assessments on the county tax bill.
Source: CA Const. Art. XIIIA (Prop 13) · County Tax Collector
Since November 2024 within ½ mile: 1 homes completed, 4 permitted, 81 proposed or in review (16 of them deed-restricted affordable).
8 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.
62 permits within ½ mile since November 2024
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-B3 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 10.6 yr (first record Apr 5, 2016), with no completion or new permit record in 10.6 yr. · $7,500 declared valuation
In "Entitled" for 8.2 yr (since Sep 12, 2018), with no new permit record in 8.2 yr. · 1 unit
Permit issued and active for 8.7 yr (first record Mar 7, 2018), with no completion or new permit record in 7.8 yr. · 1 unit · $130,000 declared valuation
In "Entitled" for 6.2 yr (since Sep 11, 2020), with no new permit record in 6.2 yr. · 1 unit
In "Applied" for 5.2 yr (since Sep 8, 2021), with no new permit record in 5.2 yr. · 1 unit · $11,000 declared valuation
In "Entitled" for 5.1 yr (since Oct 6, 2021), with no new permit record in 5.1 yr. · 1 unit
Nearby other (132 Tiburon Blvd): First appeared in published agency feed
Record 94622 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Nearby roof replacement (108 Orange St): First appeared in published agency feed
Record B49001 · 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 $1,376,137 in September 2025 to $1,394,155 in September 2026.
Source: Zillow Home Value Index (ZHVI) · Data provided by Zillow · Geography: ZIP 94901 (not a parcel appraisal)
202 Auburn St ( A D U 202 A) · 1 unit · $160,000 valuation
Records span Oct 25, 2024 to Sep 18, 2026 (1 permit).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) & HCD APR (grouped project within ½ mile)
221 Tiburon Blvd · 1 unit · $75,000 valuation
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) & HCD APR (grouped project within ½ mile)
15 Bret Harte Rd · 1 unit · $2,200 valuation
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) & HCD APR (grouped project within ½ mile)
14 Gilbert St · 1 unit · $400,000 valuation
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) & HCD APR (grouped project within ½ mile)
1 unit
Records span Jul 16, 2024 to Nov 24, 2025 (0 permits).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) & HCD APR (grouped project within ½ mile)
Annual ZIP 94901 home-value index checkpoint
Changed from $1,415,574 in September 2024 to $1,376,137 in September 2025.
Source: Zillow Home Value Index (ZHVI) · Data provided by Zillow · Geography: ZIP 94901 (not a parcel appraisal)
0 Auburn St & Woodland Ave · 79 units · 16 affordable
Records span Dec 18, 2024 to Sep 11, 2025 (16 permits).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) & HCD APR (grouped project within ½ mile)
134 Orange St (Adu 137a) · 1 unit · $20,000 valuation
Records span Aug 25, 2023 to Feb 12, 2025 (1 permit).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) & HCD APR (grouped project within ½ mile)
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) & HCD APR (grouped project within ½ mile)
Annual ZIP 94901 home-value index checkpoint
Changed from $1,407,895 in September 2023 to $1,415,574 in September 2024.
Source: Zillow Home Value Index (ZHVI) · Data provided by Zillow · Geography: ZIP 94901 (not a parcel appraisal)
Annual ZIP 94901 home-value index checkpoint
Changed from $1,475,874 in September 2022 to $1,407,895 in September 2023.
Source: Zillow Home Value Index (ZHVI) · Data provided by Zillow · Geography: ZIP 94901 (not a parcel appraisal)
22 Bret Harte Rd · 1 unit · $75,000 valuation
Records span Nov 18, 2022 to May 24, 2023 (1 permit).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) & HCD APR (grouped project within ½ mile)
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 "Applied" for 23 mo (since Dec 18, 2024), exceeding the 292d median and 313d 90th percentile for new multifamily / condos / mixed-use permits in Unincorporated Marin (n=21). High-impact scale (79 housing units, 16 deed-restricted affordable across 16 permits).
In "Applied" for 4.2 yr (since Sep 14, 2022), exceeding the 55d median and 261d 90th percentile for demolition permits in Unincorporated Marin (n=130).
In "Entitled" for 8.2 yr (since Sep 12, 2018), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121).
In "Applied" for 5.2 yr (since Sep 8, 2021), 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 Oct 6, 2021), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121).
In "Entitled" for 6.2 yr (since Sep 11, 2020), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121).
| Builder / contractor | Primary specialty | Here / ½ mi | ½ mi valuation | Citywide 24m trend |
|---|---|---|---|---|
| Crown Ridge Roofing | Roof replacement | 1 on parcel1 in ½ mi | $16,605 | 0 vs 0 prior |
| Owner Builder Recent nearby: 202 Auburn St ( A D U 202 A) (Sep 18, 2026) | Remodel / interior alteration | 13 in ½ mi | $698,000 | 226 vs 240 prior−6% |
| Owner Recent nearby: 40 Bret Harte Rd (May 19, 2016) | Remodel / interior alteration |
| 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 94901
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 ($14,950/yr) + local voter-approved bond debt ($2,243/yr) + fixed direct levies/Mello-Roos ($450/yr).
Insurance & hazard context:
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.
−$81,312/yr
Cash needed: $328,900
NOI: $9,403/yr
P&I: $7,560/mo
For $0/mo net cash flow
At $3,125/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 | $2,875/mo | −$7,135/mo | -26.0% | $12,835/mo | −$7,144/mo |
| Base (your inputs) | Your entered assumptions, 3.0%/yr rent growth | $3,125/mo | −$6,776/mo | -24.7% | $11,880/mo | −$6,608/mo |
| Optimistic (cap-limited) | +6% starting rent, 3% vacancy, 4.5%/yr rent growth (capped by AB 1482 ceiling of 8.6%/yr) | $3,313/mo | −$6,570/mo | -24.0% | $11,604/mo | −$6,199/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.
Tear off existing roof, reroof with class A composition shingles — ReRoofing
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
0.53 acres
Assessor's classification for assessment purposes. This is not zoning.
18 BRET HARTE RD
Source: County of Marin GIS (MarinMap), Parcels · Geography: parcel · Retrieved Nov 13, 2026
Search by parcel number 018-131-10. Assessed value is not market value.
Search by parcel number 018-131-10 (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.
| 5 in ½ mi |
| $230,000 |
| 25 vs 15 prior+67% |
| Glenns Home And Commercial Recent nearby: 155 Auburn St (Oct 6, 2016) | Remodel / interior alteration | 2 in ½ mi | $10,600 | 0 vs 0 prior |
| Resolute Design And Construction Recent nearby: 130 Altena St (Feb 12, 2025) | Addition (adds square footage) | 1 in ½ mi | $280,000 | 0 vs 0 prior |
| Herrera Construction Recent nearby: 148 Auburn St (Mar 4, 2025) | New garage / accessory structure | 1 in ½ mi | $150,000 | 1 vs 2 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 |
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.