124 Calle Del Arroyo
Stinson Beach 94970 · Stinson Beach · Unincorporated Marin · Coordinates: 37.90210, -122.64812
Executive Verdict · Public-Records Synthesis
Zoned C-R1 in Unincorporated Marin and mapped FEMA AO flood / CAL FIRE very high fire hazard severity zone (local responsibility area) due diligence; benchmark value $2,822,000 ($2,483,000–$3,161,000).
Upsides & Opportunities
- ✓ 1 documented municipal building permit on file
On-parcel permit history is indexed through Sep 25, 2026, 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)
Watchouts & Due Diligence
- ! FEMA Special Flood Hazard Area (AO, about 16% of the lot of lot)
Zone AO: 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)
- ! CAL FIRE Very High Fire Hazard Severity Zone (Local 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 Mar 24, 2025)
- ! 6 slow or stalled nearby projects within ½ mile
Closest lead: New home at 7 Jose Patio (0.11 mi W, 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 (~$32,903/yr at $2,822,000)
Sale triggers reassessment to 1.00% base + ~0.15% voter debt (~$2,742/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:
- 3,485 sq ft (0.08 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 124 CALLE DEL ARROYO
Zoning & Land Use
C-R1 — Residential Single Family (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADUPossible, with conditions
Zoned C-R1 (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, a single-family residential zone. Very High Fire Hazard Severity Zone (local responsibility area) covers all of the lot: SB 9 requires the project to meet the fire hazard mitigation standards. FEMA Special Flood Hazard Area (Zone AO) covers about 16% of the lot: the project must meet the National Flood Insurance Program floodplain standards, or the lot needs a map revision.
- SB 9: split into two lotsPossible, with conditions
Zoned C-R1, a single-family residential zone. The lot is 3,485 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 (local responsibility area) covers all of the lot: SB 9 requires the project to meet the fire hazard mitigation standards. FEMA Special Flood Hazard Area (Zone AO) covers about 16% of the lot: the project must meet the National Flood Insurance Program floodplain standards, or the lot needs a map revision.
Mapped Hazard Zones on This Lot
- CAL FIRE Fire Hazard Severity Zone
- Very High Fire Hazard Severity Zone (Local Responsibility Area) (all of the lot, map Mar 24, 2025)
- FEMA National Flood Hazard Layer
- Zone AO: 1% annual chance flood (Special Flood Hazard Area) (about 16% of the lot); Zone X: 0.2% annual chance flood hazard (shaded X) (about 84% of the lot) · FIRM panel 06041C0444E, effective August 15, 2017
Surrounding Rent & Value Benchmarks (Public Records)
Range: $2,483,000 – $3,161,000 · 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
- New home at 7 Jose Patio (Issued)0.11 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).
- New home at 4 Sacramento Patio (adu 4a) (Issued)0.21 mi W
Active in "Issued" for 2.6 yr (first record Apr 24, 2024) with no new permit activity recorded in 2.3 yr. High-impact scale (1 housing unit, $1,800,000 declared valuation across 1 permit).
- Accessory dwelling unit at 260 Belvedere Ave (Issued)0.45 mi E
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)0.47 mi E
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).
Entity-resolved builders & contractors in ½ mile: American Home Renewal (1 on parcel, 1 in ½ mi · Windows / doors / siding); Owner Builder (11 in ½ mi · Remodel / interior alteration); Gubbins Building (7 in ½ mi · Remodel / interior alteration); Owner (6 in ½ mi · New garage / accessory structure); 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 |
|---|---|---|---|---|---|
| B48503 | Windows / doors / siding | Issued | Iss. Sep 25, 2026 | $45,240 | Siding Replacement |