305 Bell Ln
Mill Valley 94941 · Tamalpais · Unincorporated Marin · Coordinates: 37.87583, -122.52777
Executive Verdict · Public-Records Synthesis
Zoned A2-B2 in Unincorporated Marin and mapped FEMA AE flood / CAL FIRE high fire hazard severity zone (state responsibility area) due diligence; benchmark value $2,278,000 ($2,005,000–$2,551,000).
Upsides & Opportunities
- ✓ Documented permitted upgrades (+$13,750 contributory est.)
Public building records show issued construction/renovation work on this parcel (3 total permits, latest Jun 22, 2026).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (parcel APN)
- ✓ Above-average reinvestment in Tamalpais
50 substantial renovation & housing permits over 24 months (20.5 per 1,000 parcels vs. 16.3 citywide baseline) (#3 of 22 neighborhoods).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (Tamalpais)
Watchouts & Due Diligence
- ! FEMA Special Flood Hazard Area (AE, about 3% of the lot of lot)
Zone AE: 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 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)
- ! Delayed or open permit activity on this parcel
Remodel / interior alteration (181897): Issued after 17 mo (6.2× the 83d median) — slower than 90% of remodel / interior alteration permits in Unincorporated Marin (median 83d, 90th pct 266d, n=1,054).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (review-time benchmark)
- ! 4 slow or stalled nearby projects within ½ mile
Closest lead: New home at 535 Tennessee Valley Rd (adu 531) (0.26 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)
Parcel & Assessor
- Lot size:
- 19,558 sq ft (0.45 ac)
- Assessor use:
- Tax Exempt
- Addresses on lot:
- 305 BELL LN
Zoning & Land Use
A2-B2 — Agriculture Limited (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADUCan't tell
Zoned A2-B2 (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 A2-B2 (agricultural), not a single-family residential zone.
- SB 9: split into two lotsUnlikely
Zoned A2-B2 (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 AE: 1% annual chance flood (Special Flood Hazard Area) (about 3% of the lot); Zone X: 0.2% annual chance flood hazard (shaded X) (about 17% of the lot); Zone X: minimal flood hazard (about 80% 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: $2,005,000 – $2,551,000 · Status: Off market
HUD Small Area FMR (ZIP 94941) · FY 2026
Studio $2,730 · 1BR $3,270 · 2BR $3,960 · 3BR $5,060 · 4BR $5,240
Developments Deserving Closer Investigation & Active Area Builders
- Remodel / interior alteration (181897) (Issued)On this parcel
Issued after 17 mo (6.2× the 83d median) — slower than 90% of remodel / interior alteration permits in Unincorporated Marin (median 83d, 90th pct 266d, n=1,054).
- Commercial tenant improvement (74339) (Applied)On this parcel
Pending in review for 11.4 yr (28.2× the 148d median) — slower than 90% of commercial tenant improvement permits in Unincorporated Marin (median 148d, 90th pct 443d, n=81).
- New home at 535 Tennessee Valley Rd (adu 531) (Issued)0.26 mi S
Active in "Issued" for 6 yr (first record Oct 29, 2020) with no new permit activity recorded in 4 yr. High-impact scale (1 housing unit, $800,000 declared valuation across 1 permit).
- New commercial building at 201 Flamingo Rd (aka 205) (Issued)0.37 mi N
Active in "Issued" for 11.7 yr (first record Feb 17, 2015) with no new permit activity recorded in 11.2 yr. High-impact scale ($3,938,400 declared valuation across 3 permits).
Entity-resolved builders & contractors in ½ mile: Mastec Communicaitons Group (1 on parcel, 1 in ½ mi · Remodel / interior alteration); North HVAC Services (1 on parcel, 1 in ½ mi · HVAC / heat pump); Owner Builder (55 in ½ mi · Remodel / interior alteration); Owner (42 in ½ mi · Remodel / interior alteration); International Building Investment (12 in ½ mi · Remodel / interior alteration).
Permit & Project History on This Parcel (3 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| 181897 | Remodel / interior alteration | Issued | Iss. Jun 22, 2026 | $25,000 | Install A Tuffshed For Storage 16ft X 24ft X 12hwith No Permanent Foundation. No Power Or Water Is Needed For Shed - B W… |
| B31194 | HVAC / heat pump | Issued | Iss. Sep 27, 2022 | $17,100 | Mini Split Installation — Mechanical Appliance |
| 74339 | Commercial tenant improvement | Applied | App. Jun 15, 2015 | $4,000 | Rmdl Shop Bathroom T.D. 7/3/15 Contact: Pippen - Nute Engineering 453-4480. Cancelled Per Owner 7/8/15 |