510 Fawn Dr
San Anselmo 94960 · Sleepy Hollow · Unincorporated Marin · Coordinates: 38.00327, -122.56848
Executive Verdict · Public-Records Synthesis
Zoned R1-BD in Unincorporated Marin with likely ADU & SB 9 infill eligibility and mapped CAL FIRE high fire hazard severity zone (state responsibility area) due diligence; benchmark value $1,997,000 ($1,757,000–$2,237,000).
Upsides & Opportunities
- ✓ ADU & SB 9 infill pathways screen as likely eligible
Zoned R1-BD supports ministerial ADU/JADU review plus SB 9 both two-unit development and ministerial urban lot split on a 29,447 sq ft lot.
Source: Unincorporated Marin zoning · CA Gov. Code 66314 & 65852.21
- ✓ 4 documented municipal building permits on file
On-parcel permit history is indexed through Oct 15, 2021, 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 Sleepy Hollow
32 substantial renovation & housing permits over 24 months (32.7 per 1,000 parcels vs. 16.4 citywide baseline) (#4 of 22 neighborhoods).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (Sleepy Hollow)
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 High Fire Hazard Severity Zone (State Responsibility Area) (about 2% 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: New home at 666 Fawn Dr (0.17 mi SE, applied). 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 (~$23,416/yr at $1,997,000)
Sale triggers reassessment to 1.00% base + ~0.15% voter debt (~$1,951/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:
- 29,447 sq ft (0.68 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 510 FAWN DR
Zoning & Land Use
R1-BD — Residential Single Family (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned R1-BD (single-family residential): state law allows ADUs where homes are allowed.
- SB 9: two homes on the lotLikely eligible
Zoned R1-BD, a single-family residential zone.
- SB 9: split into two lotsLikely eligible
Zoned R1-BD, a single-family residential zone. The lot is 29,447 sq ft by the assessor, room for two lots of at least 1,200 sq ft, each at least 40% of the original.
Mapped Hazard Zones on This Lot
- CAL FIRE Fire Hazard Severity Zone
- High Fire Hazard Severity Zone (State Responsibility Area) (about 2% of the lot, map Apr 1, 2024); Moderate Fire Hazard Severity Zone (State Responsibility Area) (about 98% of the lot, map Apr 1, 2024)
- FEMA National Flood Hazard Layer
- Zone X: minimal flood hazard (all of the lot) · FIRM panel 06041C0289D, effective May 4, 2009
- CGS Alquist-Priolo Earthquake Fault Zone
- Not in an Alquist-Priolo Earthquake Fault Zone
Surrounding Rent & Value Benchmarks (Public Records)
Range: $1,757,000 – $2,237,000 · Status: Off market
HUD Small Area FMR (ZIP 94960) · FY 2026
Studio $2,510 · 1BR $3,010 · 2BR $3,640 · 3BR $4,650 · 4BR $4,820
Developments Deserving Closer Investigation & Active Area Builders
- New home at 666 Fawn Dr (Applied)0.17 mi SE
In "Applied" for 7.5 yr (since Apr 29, 2019), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121). High-impact scale (1 housing unit, $1,000,000 declared valuation across 1 permit).
- New home at 830 Butterfield Rd (Issued)0.32 mi W
Active in "Issued" for 8.3 yr (first record Aug 9, 2018) with no new permit activity recorded in 7.6 yr. High-impact scale (1 housing unit, $1,097,000 declared valuation across 2 permits).
- New home at 116 Holstein Rd (Issued)0.49 mi S
Active in "Issued" for 12.9 yr (first record Dec 24, 2013) with no new permit activity recorded in 12.4 yr. High-impact scale (1 housing unit, $800,000 declared valuation across 1 permit).
- Accessory dwelling unit at 178 Deer Hollow Rd (Applied)0.28 mi S
In "Applied" for 5.5 yr (since May 18, 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: Rwr Construction (1 on parcel, 1 in ½ mi · Other); Bay Area Underpinning (1 on parcel, 1 in ½ mi · General repair); Jemico (1 on parcel, 1 in ½ mi · Windows / doors / siding); Haddon Heating And Cooling (1 on parcel, 1 in ½ mi · HVAC / heat pump); Owner Builder (24 in ½ mi · Remodel / interior alteration).
Permit & Project History on This Parcel (4 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| B27428 | Windows / doors / siding | Issued | Iss. Oct 15, 2021 | $9,013 | Replacing 1 full frame patio door. — Non-structural Door/Window Replacement |
| 169589 | General repair | Issued | Iss. Oct 11, 2021 | $48,000 | Rem/Repl Part Foundation & Install Push Piers For Stabilization |
| B20859 | HVAC / heat pump | Issued | Iss. Jan 27, 2020 | $5,000 | Furnace & Duct Replacement Only — Replace Ductwork, Replace Mechanical Appliance |
| 144946 | Other | Issued | Iss. Nov 17, 2014 | $54,285 | Voluntary Foundation Upgr @ Guest House T.D. 11/5/14 |