128 Auburn St
San Rafael 94901 · California Park · Unincorporated Marin · Coordinates: 37.95836, -122.51336
Executive Verdict · Public-Records Synthesis
Zoned R1 in Unincorporated Marin with likely ADU & SB 9 infill eligibility and zero mapped flood, fire, or fault hazard overlaps; benchmark value $1,380,000 ($1,214,000–$1,546,000).
Upsides & Opportunities
- ✓ ADU & SB 9 infill pathways screen as likely eligible
Zoned R1 supports ministerial ADU/JADU review plus SB 9 both two-unit development and ministerial urban lot split on a 7,362 sq ft lot. Local precedent is active with 3 ADU permits within ¼ mile over the last 36 months.
Source: Unincorporated Marin zoning · CA Gov. Code 66314 & 65852.21
- ✓ Documented permitted upgrades (+$7,040 contributory est.)
Public building records show issued construction/renovation work on this parcel (2 total permits, latest Jun 20, 2023).
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)
- ! 6 slow or stalled nearby projects within ½ mile
Closest lead: 79 new homes at 0 Auburn St & Woodland Ave (0.1 mi E, 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 (~$16,320/yr at $1,380,000)
Sale triggers reassessment to 1.00% base + ~0.15% voter debt (~$1,360/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:
- 7,362 sq ft (0.17 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 128 AUBURN ST
Zoning & Land Use
R1 — Residential Single Family (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned R1 (single-family residential): state law allows ADUs where homes are allowed.
- SB 9: two homes on the lotLikely eligible
Zoned R1, a single-family residential zone.
- SB 9: split into two lotsLikely eligible
Zoned R1, a single-family residential zone. The lot is 7,362 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
- Not in a State-mapped fire hazard severity zone
- FEMA National Flood Hazard Layer
- Zone X: minimal flood hazard (all of the lot) · FIRM panel 06041C0459F, 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: $1,214,000 – $1,546,000 · Status: Off market
HUD Small Area FMR (ZIP 94901) · FY 2026
Studio $2,150 · 1BR $2,580 · 2BR $3,120 · 3BR $3,990 · 4BR $4,130
Developments Deserving Closer Investigation & Active Area Builders
- 79 new homes at 0 Auburn St & Woodland Ave (Applied)0.1 mi E
In "Applied" for 23 mo (since Dec 18, 2024), exceeding the 292d median and 313d 90th percentile for new multifamily / condos / mixed-use permits in Unincorporated Marin (n=21). High-impact scale (79 housing units, 16 deed-restricted affordable across 16 permits).
- 71 new homes (Entitled)0.5 mi NE
In "Entitled" for 4.5 yr (since May 10, 2022), exceeding the 292d median and 313d 90th percentile for new multifamily / condos / mixed-use permits in Unincorporated Marin (n=21). High-impact scale (71 housing units, 6 deed-restricted affordable across 0 permits).
- Accessory dwelling unit at 134 Orange St (Applied)360 ft SW
In "Applied" for 5.2 yr (since Sep 8, 2021), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121).
- New home (Entitled)490 ft NW
In "Entitled" for 6.2 yr (since Sep 11, 2020), 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: Contreras Roofing (1 on parcel, 1 in ½ mi · Roof replacement); Lumio Hx (1 on parcel, 1 in ½ mi · Solar / battery storage); Owner Builder (14 in ½ mi · Remodel / interior alteration); Owner (5 in ½ mi · Remodel / interior alteration); Glenns Home And Commercial (2 in ½ mi · Remodel / interior alteration).
Permit & Project History on This Parcel (2 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| B34388 | Roof replacement | Issued | Iss. Jun 20, 2023 | $15,300 | remove one layer of tar and gravel roof approximately 1600sq feet over existing substrate install 1/4 den deck class A f… |
| B33805 | Solar / battery storage | Issued | Iss. May 9, 2023 | $15,000 | SFR ROOF MOUNTED PV SYSTEM, COMP, 15 PANELS, 6.000 KW DC |