San Quentin 94964 · San Quentin · APN 018-164-03 · Unincorporated Marin
Zoned RSP-5.8-BFC in Unincorporated Marin with likely ministerial ADU eligibility and mapped FEMA VE flood due diligence; benchmark value $1,411,000 ($1,199,000–$1,623,000).
Zone RSP-5.8-BFC allows residential use qualifying for ministerial ADU review under state law.
Source: Unincorporated Marin zoning · CA Gov. Code 66314
Public building records show issued construction/renovation work on this parcel (3 total permits, latest Sep 18, 2017).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (parcel APN)
Zone VE: 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.
12 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
$1,411,000
Benchmark range: $1,199,000 – $1,623,000
Closest lead: New home at 22 Mckenzie St (300 ft N, issued). 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 (~$1,390/mo). Confirm exact Mello-Roos / CFD special assessments on the county tax bill.
Source: CA Const. Art. XIIIA (Prop 13) · County Tax Collector
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 RSP-5.8-BFC 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 3.9 yr (first record Dec 27, 2022), with no completion or new permit record in 2.8 yr. · 1 unit · $850,000 declared valuation
Nearby remodel / interior alteration (130 Le Cante Dr): Contractor changed from (blank) to BOLT DOWN THE BAY AREA
Record 182711 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
22 Mckenzie St · 1 unit · $850,000 valuation
Records span Dec 27, 2022 to Jan 22, 2024 (1 permit).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) & HCD APR (grouped project within ½ mile)
38 Main St (Aka 38a) · 1 unit · $225,000 valuation
Records span Aug 29, 2022 to Apr 10, 2023 (1 permit).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) & HCD APR (grouped project within ½ mile)
Remodel / interior alteration permit issued (156530)
Recorded status: Issued
Conv Of Bsmt (Struct)To Liv Sp T.D. 8/15/17 · Declared valuation: $15,000 · Contractor: Hoffmann Construction, Inc.
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Geography: parcel
Remodel / interior alteration permit application filed (156530)
Current status: Issued
Conv Of Bsmt (Struct)To Liv Sp T.D. 8/15/17 · Declared valuation: $15,000 · Contractor: Hoffmann Construction, Inc.
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Geography: parcel
HVAC / heat pump permit issued (152369)
Recorded status: Issued
Install Mini Split System (Hvac) · Declared valuation: $2,500 · Contractor: Ongaro, Ernest & Sons, Inc.
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Geography: parcel
Plumbing / water heater / sewer permit issued (147666)
Recorded status: Issued
Replace Tank Water Heater With Tankless Water Heater · Declared valuation: $4,200 · Contractor: Ongaro, Ernest & Sons, Inc.
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Geography: parcel
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 →Active in "Issued" for 3.9 yr (first record Dec 27, 2022) with no new permit activity recorded in 2.8 yr. High-impact scale (1 housing unit, $850,000 declared valuation across 1 permit).
| Builder / contractor | Primary specialty | Here / ½ mi | ½ mi valuation | Citywide 24m trend |
|---|---|---|---|---|
| Ongaro Ernest And Sons | HVAC / heat pump | 2 on parcel2 in ½ mi | $6,700 | 0 vs 0 prior |
| Hoffmann Construction | Remodel / interior alteration | 1 on parcel1 in ½ mi | $15,000 | 1 vs 0 prior |
| James Flanagan Builder Recent nearby: 18 (A) Main St (Nov 15, 2017) | New garage / accessory structure | 2 in ½ mi | $56,000 | 0 vs 1 prior |
| Rodd Renovations Recent nearby: 22 Mckenzie St (Jan 22, 2024) | New single-family home | 1 in ½ mi | $850,000 |
| 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 94964
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 ($14,100/yr) + local voter-approved bond debt ($2,115/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.
−$71,388/yr
Cash needed: $310,200
NOI: $14,168/yr
P&I: $7,130/mo
For $0/mo net cash flow
At $3,675/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 | $3,381/mo | −$6,371/mo | -24.6% | $12,275/mo | −$6,363/mo |
| Base (your inputs) | Your entered assumptions, 3.0%/yr rent growth | $3,675/mo | −$5,949/mo | -23.0% | $11,361/mo | −$5,732/mo |
| Optimistic (cap-limited) | +6% starting rent, 3% vacancy, 4.5%/yr rent growth (capped by AB 1482 ceiling of 8.6%/yr) | $3,896/mo | −$5,706/mo | -22.1% | $11,097/mo | −$5,252/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.
Conv Of Bsmt (Struct)To Liv Sp T.D. 8/15/17
Install Mini Split System (Hvac)
Replace Tank Water Heater With Tankless Water Heater
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
0.17 acres
Assessor's classification for assessment purposes. This is not zoning.
23 MAIN ST
Source: County of Marin GIS (MarinMap), Parcels · Geography: parcel · Retrieved Nov 13, 2026
Search by parcel number 018-164-03. Assessed value is not market value.
Search by parcel number 018-164-03 (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 |
| Bolt Down The Bay Area Recent nearby: 130 Le Cante Dr (Oct 12, 2026) | Remodel / interior alteration | 1 in ½ mi | $287,000 | 5 vs 0 prior |
| Kearney Construction Recent nearby: 38 Main St (Aka 38a) (Apr 10, 2023) | Accessory dwelling unit (new or conversion) | 1 in ½ mi | $225,000 | 2 vs 3 prior |
| Guthrie Construction Recent nearby: 80 Heron Ct (Mar 7, 2024) | Remodel / interior alteration | 1 in ½ mi | $196,000 | 0 vs 3 prior |
| 316 |
| 103d |
| 160d |
| 249d |
| 440d |
| 157d(vs 167d prior) |
| Remodel / interior alterationOn this parcel | 1,054 | 36d | 83d | 148d | 266d | 112d(vs 77d prior) |
| Commercial tenant improvement | 81 | 99d | 148d | 233d | 443d | 152d(vs 150d prior) |
| HVAC / heat pumpOn this parcel | 2,946 | 0d | 0d | 0d | 0d | 0d |
| Plumbing / water heater / sewerOn this parcel | 2,211 | 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.