21 Ahab Dr
Sausalito 94965 · Muir Beach · Unincorporated Marin · Coordinates: 37.86123, -122.58103
Executive Verdict · Public-Records Synthesis
Zoned C-RA-B4 in Unincorporated Marin and mapped CAL FIRE very high fire hazard severity zone (state responsibility area) due diligence; benchmark value $1,844,000 ($1,623,000–$2,065,000).
Upsides & Opportunities
- ✓ Documented permitted upgrades (+$11,761 contributory est.)
Public building records show issued construction/renovation work on this parcel (2 total permits, latest Oct 29, 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)
- ! 4 slow or stalled nearby projects within ½ mile
Closest lead: Accessory dwelling unit at 69 Starbuck Dr (adu 69a) (0.19 mi NE, 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 (~$21,656/yr at $1,844,000)
Sale triggers reassessment to 1.00% base + ~0.15% voter debt (~$1,805/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:
- 27,443 sq ft (0.63 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 21 AHAB DR
Zoning & Land Use
C-RA-B4 — Residential Agriculture (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADUPossible, with conditions
Zoned C-RA-B4 (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 lotCan't tell
Zoned C-RA-B4 (single-family residential): we can't tell whether it counts as a single-family zone for SB 9. Residential agriculture, estate and restricted: large-lot residential; confirm SB 9 with the county.
- SB 9: split into two lotsCan't tell
Zoned C-RA-B4 (single-family residential): we can't tell whether it counts as a single-family zone for SB 9. Residential agriculture, estate and restricted: large-lot residential; confirm SB 9 with the county.
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 06041C0505E, 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: $1,623,000 – $2,065,000 · 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
- Accessory dwelling unit at 69 Starbuck Dr (adu 69a) (Issued)0.19 mi NE
Active in "Issued" for 2.5 yr (first record May 28, 2024) with no new permit activity recorded in 20 mo. High-impact scale (1 housing unit, $1,200,000 declared valuation across 1 permit).
- Demolition at 40 Starbuck Dr (Issued)0.13 mi N
Active in "Issued" for 9.8 yr (first record Jan 30, 2017) with no new permit activity recorded in 9.8 yr.
- New commercial building at 87 Seacape Dr (Issued)0.26 mi NW
Active in "Issued" for 2.6 yr (first record Apr 17, 2024) with no new permit activity recorded in 19 mo.
- Accessory dwelling unit at 77 Starbuck Dr (Applied)0.22 mi NE
In "Applied" for 18 mo (since May 28, 2025), exceeding the 253d median and 456d 75th percentile for new single-family home permits in Unincorporated Marin (n=121).
Entity-resolved builders & contractors in ½ mile: Sun First! (1 on parcel, 1 in ½ mi · Solar / battery storage); Mountain House Mechanical (1 on parcel, 1 in ½ mi · HVAC / heat pump); Owner Builder (11 in ½ mi · Remodel / interior alteration); Owner (6 in ½ mi · New garage / accessory structure); Sidney Builders (3 in ½ mi · Addition (adds square footage)).
Permit & Project History on This Parcel (2 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| B44585 | Solar / battery storage | Issued | Iss. Oct 29, 2025 | $27,224 | Install (8) roof mounted PV solar modules and (1) Powerwall 3 with a Tesla Backup Switch |
| B43507 | HVAC / heat pump | Issued | Iss. Aug 18, 2025 | $10,083 | Install an 80 gallon Heat Pump Water Heater — Mechanical Appliance |