80 De Silva Island Dr
Mill Valley 94941 · Strawberry · Unincorporated Marin · Coordinates: 37.88778, -122.51416
Executive Verdict · Public-Records Synthesis
Zoned RMP-1.5-BFC in Unincorporated Marin with likely ministerial ADU eligibility and zero mapped flood, fire, or fault hazard overlaps; benchmark value $2,136,000 ($1,880,000–$2,392,000).
Upsides & Opportunities
- ✓ Ministerial ADU / JADU pathway likely eligible
Zone RMP-1.5-BFC allows residential use qualifying for ministerial ADU review under state law.
Source: Unincorporated Marin zoning · CA Gov. Code 66314
- ✓ Documented permitted upgrades (+$8,800 contributory est.)
Public building records show issued construction/renovation work on this parcel (3 total permits, latest Nov 4, 2021).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (parcel APN)
- ✓ Above-average reinvestment in Strawberry
43 substantial renovation & housing permits over 24 months (28.4 per 1,000 parcels vs. 16.4 citywide baseline) (#1 of 22 neighborhoods).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (Strawberry)
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: New home at 218 Meda Ln (0.48 mi NE, 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 (~$25,014/yr at $2,136,000)
Sale triggers reassessment to 1.00% base + ~0.15% voter debt (~$2,085/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:
- 1,176 sq ft (0.03 ac)
- Assessor use:
- Single Family Attached
- Addresses on lot:
- 80 DE SILVA ISLAND DR
Zoning & Land Use
RMP-1.5-BFC — Residential Multiple Planned (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned RMP-1.5-BFC (multifamily residential): state law allows ADUs where homes are allowed. On a multifamily lot the state allowance is different: ADUs in non-living space of the building, plus up to eight detached ADUs.
- SB 9: two homes on the lotUnlikely
Zoned RMP-1.5-BFC (multifamily residential), not a single-family residential zone.
- SB 9: split into two lotsUnlikely
Zoned RMP-1.5-BFC (multifamily residential), not a single-family residential zone.
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 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: $1,880,000 – $2,392,000 · 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
Nearby Activity (½ mile radius, since November 2024)
1 active or recent development project and 126 total building permits recorded within ½ mile.
- New construction1 permit
- Demolition1 permit
- Additions & renovations12 permits
- Building systems85 permits
- Repairs14 permits
- Other13 permits
Developments Deserving Closer Investigation & Active Area Builders
- New home at 218 Meda Ln (Applied)0.48 mi NE
In "Applied" for 6.5 yr (since Apr 30, 2020), 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, $850,000 declared valuation across 1 permit).
- Accessory dwelling unit at 25 Vista Del Sol (Applied)0.35 mi N
In "Applied" for 2.1 yr (since Oct 11, 2024), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121).
- Accessory dwelling unit at 315 Richardson Dr (Applied)0.42 mi NE
In "Applied" for 2 yr (since Oct 31, 2024), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121).
- Accessory dwelling unit at 308 Richardson Dr (Applied)0.47 mi NE
In "Applied" for 7.7 yr (since Mar 14, 2019), 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: Owner (1 on parcel, 6 in ½ mi · Remodel / interior alteration); Saarman Construction (1 on parcel, 1 in ½ mi · Windows / doors / siding); Tyler Jones (1 on parcel, 1 in ½ mi · Electrical / panel); Owner Builder (8 in ½ mi · Remodel / interior alteration); Wci Gc (3 in ½ mi · Commercial tenant improvement).
Permit & Project History on This Parcel (3 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| B27632 | Electrical / panel | Issued | Iss. Nov 4, 2021 | $200 | Install new 220v/20amp electrical outlet in stairway. — New Circuits / Outlets |
| 169387 | Remodel / interior alteration | Issued | Iss. Sep 20, 2021 | $20,000 | Non-Structural Interior Remodel, Bath - Express |
| B26026 | Windows / doors / siding | Issued | Iss. Jul 6, 2021 | $28,762 | Saarman Construction will be removing and replacing one Jeld Wen Wood Window and install waterproofing and sealants as r… |