605 Horseshoe Hill Rd
Bolinas 94924 · Bolinas · Unincorporated Marin · Coordinates: 37.93393, -122.70397
Executive Verdict · Public-Records Synthesis
Zoned C-APZ-60 in Unincorporated Marin and mapped CAL FIRE high fire hazard severity zone (state responsibility area) / Alquist-Priolo fault due diligence; benchmark value $1,981,000 ($1,743,000–$2,219,000).
Upsides & Opportunities
- ✓ Documented permitted upgrades (+$12,819 contributory est.)
Public building records show issued construction/renovation work on this parcel (2 total permits, latest Sep 23, 2026).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (parcel APN)
Watchouts & Due Diligence
- ! Mapped flood awareness zone (Zone X: minimal flood hazard)
about 1% 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)
- ! CAL FIRE High Fire Hazard Severity Zone (State Responsibility Area) (all of the lot of lot)
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 Apr 1, 2024)
- ! Alquist-Priolo Earthquake Fault Zone (all of the lot of lot)
Intersects a State-mapped surface fault rupture zone. Adding habitable structures or subdividing typically requires a site-specific geologic fault investigation.
Source: California Geological Survey Alquist-Priolo Zones
- ! Year 1 Prop 13 tax reset (~$23,232/yr at $1,981,000)
Sale triggers reassessment to 1.00% base + ~0.15% voter debt (~$1,936/mo). Confirm exact Mello-Roos / CFD special assessments on the county tax bill.
Source: CA Const. Art. XIIIA (Prop 13) · County Tax Collector
Parcel & Assessor
- Lot size:
- 2,962,298 sq ft (68.01 ac)
- Assessor use:
- Rural - Improved
- Addresses on lot:
- 605 HORSESHOE HILL RD
Zoning & Land Use
C-APZ-60 — Agriculture Production Zone (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADUCan't tell
Zoned C-APZ-60 (agricultural): ADUs are allowed if the zone allows a home, which depends on the zone's rules.
- SB 9: two homes on the lotUnlikely
Zoned C-APZ-60 (agricultural), not a single-family residential zone.
- SB 9: split into two lotsUnlikely
Zoned C-APZ-60 (agricultural), not a single-family residential zone.
Mapped Hazard Zones on This Lot
- CAL FIRE Fire Hazard Severity Zone
- High Fire Hazard Severity Zone (State Responsibility Area) (all of the lot, map Apr 1, 2024)
- FEMA National Flood Hazard Layer
- Zone X: minimal flood hazard (about 1% of the lot); Zone X: minimal flood hazard (about 99% of the lot) · FIRM panel 06041C0440E, effective August 15, 2017
- CGS Alquist-Priolo Earthquake Fault Zone
- Alquist-Priolo Earthquake Fault Zone (Bolinas quadrangle) (all of the lot)
Surrounding Rent & Value Benchmarks (Public Records)
Range: $1,743,000 – $2,219,000 · Status: Off market
HUD Small Area FMR (ZIP 94924) · FY 2026
Studio $2,050 · 1BR $2,510 · 2BR $2,990 · 3BR $3,730 · 4BR $3,960
Developments Deserving Closer Investigation & Active Area Builders
Entity-resolved builders & contractors in ½ mile: Sonomarin Solar_inc (2 on parcel, 2 in ½ mi · Electrical / panel); Rj Heffelfinger Construction (2 in ½ mi · Addition (adds square footage)); Bracelin (1 in ½ mi · New garage / accessory structure).
Permit & Project History on This Parcel (2 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| B48465 | Electrical / panel | Issued | Iss. Sep 23, 2026 | $4,200 | Service Upgrade |
| B41332 | Solar / battery storage | Issued | Iss. Feb 20, 2025 | $29,673 | Photovoltaic-Residential Flush Room Mount, Grid Tied ESS Installation with (2) Tesla Powerwall 3 ESS Units |