257 Donahue St
Sausalito 94965 · Marin City · Unincorporated Marin · Coordinates: 37.87605, -122.51382
Executive Verdict · Public-Records Synthesis
Zoned RMP-10 in Unincorporated Marin with likely ministerial ADU eligibility and mapped CAL FIRE moderate fire hazard severity zone (state responsibility area) due diligence; benchmark value $1,519,000 ($1,337,000–$1,701,000).
Upsides & Opportunities
- ✓ Ministerial ADU / JADU pathway likely eligible
Zone RMP-10 allows residential use qualifying for ministerial ADU review under state law.
Source: Unincorporated Marin zoning · CA Gov. Code 66314
- ✓ 4 documented municipal building permits on file
On-parcel permit history is indexed through Feb 13, 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)
- ✓ Above-average reinvestment in Marin City
21 substantial renovation & housing permits over 24 months (40.5 per 1,000 parcels vs. 16.3 citywide baseline) (#14 of 22 neighborhoods).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (Marin City)
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 Moderate 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: 74 new homes at 825 Drake Ave (0.12 mi S, 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 (~$17,919/yr at $1,519,000)
Sale triggers reassessment to 1.00% base + ~0.15% voter debt (~$1,493/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:
- 610 sq ft (0.01 ac)
- Assessor use:
- Single Family Attached
- Addresses on lot:
- 257 DONAHUE ST
Zoning & Land Use
RMP-10 — Residential Multiple Planned (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned RMP-10 (multifamily residential): state law allows ADUs where homes are allowed. On a multifamily lot the state allowance is different: ADUs in non-living space of the building, plus up to eight detached ADUs.
- SB 9: two homes on the lotUnlikely
Zoned RMP-10 (multifamily residential), not a single-family residential zone.
- SB 9: split into two lotsUnlikely
Zoned RMP-10 (multifamily residential), not a single-family residential zone.
Mapped Hazard Zones on This Lot
- CAL FIRE Fire Hazard Severity Zone
- Moderate 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 06041C0469F, effective March 16, 2016
- CGS Alquist-Priolo Earthquake Fault Zone
- Not in an Alquist-Priolo Earthquake Fault Zone
Surrounding Rent & Value Benchmarks (Public Records)
Range: $1,337,000 – $1,701,000 · Status: Off market
HUD Small Area FMR (ZIP 94965) · FY 2026
Studio $2,720 · 1BR $3,260 · 2BR $3,950 · 3BR $5,050 · 4BR $5,230
Developments Deserving Closer Investigation & Active Area Builders
- 74 new homes at 825 Drake Ave (Issued)0.12 mi S
Active in "Issued" for 6 yr (first record Nov 30, 2020) with no new permit activity recorded in 3.5 yr. High-impact scale (74 housing units, $8,731,920 declared valuation across 1 permit).
- New home at 25 Burgess Ct (adu #23) (Issued)0.3 mi S
Active in "Issued" for 6.9 yr (first record Dec 30, 2019) with no new permit activity recorded in 5.1 yr. High-impact scale (1 housing unit, $2,200,000 declared valuation across 1 permit).
- New home (Entitled)0.41 mi S
In "Entitled" for 5.5 yr (since May 12, 2021), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121).
- New home (Entitled)0.45 mi S
In "Entitled" for 5.5 yr (since Apr 28, 2021), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121).
Entity-resolved builders & contractors in ½ mile: Talley Electric Service (2 on parcel, 2 in ½ mi · Electrical / panel); Save Energy (1 on parcel, 1 in ½ mi · Windows / doors / siding); Integrity Electric (1 on parcel, 1 in ½ mi · Electrical / panel); Owner Builder (31 in ½ mi · Remodel / interior alteration); Owner (25 in ½ mi · Remodel / interior alteration).
Permit & Project History on This Parcel (4 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| B45859 | Electrical / panel | Issued | Iss. Feb 13, 2026 | $2,250 | Service Upgrade |
| B45855 | Electrical / panel | Issued | Iss. Feb 12, 2026 | $2,250 | Service Upgrade |
| B17678 | Electrical / panel | Issued | Iss. May 3, 2019 | $3,131 | In the mechanical room install 200A (NEMA 1) interior sub panel with 40 circuit breaker space, — Service Upgrade |
| 146585 | Windows / doors / siding | Issued | Iss. Apr 8, 2015 | $9,821 | Replace Windows |