878 Estancia Way
San Rafael 94903 · Santa Venetia · Unincorporated Marin · Coordinates: 38.01576, -122.51186
Executive Verdict · Public-Records Synthesis
Zoned R1-B1 in Unincorporated Marin with likely ministerial ADU eligibility and mapped FEMA AE flood due diligence; benchmark value $1,173,000 ($1,032,000–$1,314,000).
Upsides & Opportunities
- ✓ Ministerial ADU / JADU pathway likely eligible
Zone R1-B1 allows residential use qualifying for ministerial ADU review under state law (2 ADU permits permitted within ¼ mile in 36 months).
Source: Unincorporated Marin zoning · CA Gov. Code 66314
- ✓ 1 documented municipal building permit on file
On-parcel permit history is indexed through Jun 28, 2022, 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 (AE, all 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)
- ! 6 slow or stalled nearby projects within ½ mile
Closest lead: New home at 35 Pt Gallinas Rd (0.25 mi E, 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 (~$13,940/yr at $1,173,000)
Sale triggers reassessment to 1.00% base + ~0.15% voter debt (~$1,162/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:
- 6,360 sq ft (0.15 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 878 ESTANCIA WAY
Zoning & Land Use
R1-B1 — Residential Single Family (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned R1-B1 (single-family residential): state law allows ADUs where homes are allowed.
- SB 9: two homes on the lotPossible, with conditions
Zoned R1-B1, a single-family residential zone. FEMA Special Flood Hazard Area (Zone AE) covers all 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 R1-B1, a single-family residential zone. The lot is 6,360 sq ft by the assessor, room for two lots of at least 1,200 sq ft, each at least 40% of the original. FEMA Special Flood Hazard Area (Zone AE) covers all 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
- Not in a State-mapped fire hazard severity zone
- FEMA National Flood Hazard Layer
- Zone AE: 1% annual chance flood (Special Flood Hazard Area) (all of the lot) · FIRM panel 06041C0294E, 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: $1,032,000 – $1,314,000 · Status: Off market
HUD Small Area FMR (ZIP 94903) · FY 2026
Studio $2,880 · 1BR $3,450 · 2BR $4,180 · 3BR $5,340 · 4BR $5,530
Nearby Activity (½ mile radius, since November 2024)
3 active or recent development projects (2 housing units across completed, permitted, and pipeline stages) and 172 total building permits recorded within ½ mile.
- New construction2 permits
- Adds housing (ADU)2 permits (2 units)
- Demolition1 permit
- Additions & renovations5 permits
- Building systems132 permits
- Repairs3 permits
- Other27 permits
Developments Deserving Closer Investigation & Active Area Builders
- New home at 35 Pt Gallinas Rd (Issued)0.25 mi E
Active in "Issued" for 9.5 yr (first record May 24, 2017) with no new permit activity recorded in 9.3 yr. High-impact scale (1 housing unit, $2,367,450 declared valuation across 1 permit).
- Accessory dwelling unit at 835 Rosal Way (Applied)410 ft NW
In "Applied" for 2.2 yr (since Sep 11, 2024), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121).
- Demolition at 1145 Adrian Way (Applied)0.15 mi S
In "Applied" for 4.9 yr (since Dec 2, 2021), exceeding the 55d median and 261d 90th percentile for demolition permits in Unincorporated Marin (n=130).
- Accessory dwelling unit at 798 Hacienda Way (Applied)0.22 mi W
In "Applied" for 11.1 yr (since Oct 5, 2015), 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: Richard Osorio Heating And Air (1 on parcel, 1 in ½ mi · HVAC / heat pump); Owner Builder (18 in ½ mi · Remodel / interior alteration); Owner (11 in ½ mi · Remodel / interior alteration); Lsr Maintenancellc (5 in ½ mi · Remodel / interior alteration); Gustavo Brooks Construction (4 in ½ mi · Remodel / interior alteration).
Permit & Project History on This Parcel (1 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| B30205 | HVAC / heat pump | Issued | Iss. Jun 28, 2022 | $22,166 | Install ductless unit. Install air handlers to 3 rooms. — Mechanical Appliance |