380 Belvedere Ave
Stinson Beach 94970 · Stinson Beach · Unincorporated Marin · Coordinates: 37.90357, -122.64275
Executive Verdict · Public-Records Synthesis
Zoned C-R1-B3 in Unincorporated Marin and mapped CAL FIRE very high fire hazard severity zone (state responsibility area) due diligence; benchmark value $3,286,000 ($2,892,000–$3,680,000).
Upsides & Opportunities
- ✓ Documented permitted upgrades (+$17,280 contributory est.)
Public building records show issued construction/renovation work on this parcel (1 total permit, latest Nov 24, 2025).
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)
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)
- ! CAL FIRE Very 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)
- ! 6 slow or stalled nearby projects within ½ mile
Closest lead: Accessory dwelling unit at 260 Belvedere Ave (0.2 mi SE, 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)
- ! Year 1 Prop 13 tax reset (~$38,239/yr at $3,286,000)
Sale triggers reassessment to 1.00% base + ~0.15% voter debt (~$3,187/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:
- 23,087 sq ft (0.53 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 380 BELVEDERE AVE
Zoning & Land Use
C-R1-B3 — Residential Single Family (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADUPossible, with conditions
Zoned C-R1-B3 (single-family residential): state law allows ADUs where homes are allowed. Very High Fire Hazard Severity Zone covers all of the lot: cities may limit ADUs here for fire safety and evacuation.
- SB 9: two homes on the lotPossible, with conditions
Zoned C-R1-B3, a single-family residential zone. Very High Fire Hazard Severity Zone (State responsibility area) covers all of the lot: SB 9 requires the project to meet the fire hazard mitigation standards.
- SB 9: split into two lotsPossible, with conditions
Zoned C-R1-B3, a single-family residential zone. The lot is 23,087 sq ft by the assessor, room for two lots of at least 1,200 sq ft, each at least 40% of the original. Very High Fire Hazard Severity Zone (State responsibility area) covers all of the lot: SB 9 requires the project to meet the fire hazard mitigation standards.
Mapped Hazard Zones on This Lot
- CAL FIRE Fire Hazard Severity Zone
- Very 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 (all of the lot) · FIRM panel 06041C0444E, effective August 15, 2017
- CGS Alquist-Priolo Earthquake Fault Zone
- Not in an Alquist-Priolo Earthquake Fault Zone
Surrounding Rent & Value Benchmarks (Public Records)
Range: $2,892,000 – $3,680,000 · Status: Off market
HUD Small Area FMR (ZIP 94970) · FY 2026
Studio $2,090 · 1BR $2,510 · 2BR $3,030 · 3BR $3,870 · 4BR $4,010
Developments Deserving Closer Investigation & Active Area Builders
- Accessory dwelling unit at 260 Belvedere Ave (Issued)0.2 mi SE
Active in "Issued" for 4.9 yr (first record Dec 16, 2021) with no new permit activity recorded in 22 mo. High-impact scale (1 housing unit, $2,000,000 declared valuation across 1 permit).
- New home at 25 Lincoln Ave (Issued)0.29 mi SE
Active in "Issued" for 7.3 yr (first record Jul 22, 2019) with no new permit activity recorded in 7.1 yr. High-impact scale (1 housing unit, $969,000 declared valuation across 1 permit).
- Mixed-use development at 3466 State Route 1 & (Issued)0.4 mi SE
Active in "Issued" for 6.1 yr (first record Sep 23, 2020) with no new permit activity recorded in 5.1 yr. High-impact scale (1 housing unit, $1,000,000 declared valuation across 2 permits).
- New home at 7 Jose Patio (Issued)0.42 mi W
Active in "Issued" for 3.5 yr (first record May 16, 2023) with no new permit activity recorded in 2.4 yr. High-impact scale (1 housing unit, $1,750,000 declared valuation across 1 permit).
Entity-resolved builders & contractors in ½ mile: Nexus Energy (1 on parcel, 1 in ½ mi · Solar / battery storage); Owner Builder (17 in ½ mi · Commercial tenant improvement); Owner (8 in ½ mi · New garage / accessory structure); Gubbins Building (5 in ½ mi · Remodel / interior alteration); George T Flynn Construction (4 in ½ mi · New garage / accessory structure).
Permit & Project History on This Parcel (1 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| B44888 | Solar / battery storage | Issued | Iss. Nov 24, 2025 | $54,344 | Install 7.04kw solar system, 16 panels 16 micros 2 enphase batteries |