83 De Silva Island Dr
Mill Valley 94941 · Strawberry · Unincorporated Marin · Coordinates: 37.88785, -122.51398
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 $2,190,000 ($1,927,000–$2,453,000).
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 (+$63,360 contributory est.)
Public building records show issued construction/renovation work on this parcel (4 total permits, latest Aug 4, 2025).
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 (0.47 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 (~$25,635/yr at $2,190,000)
Sale triggers reassessment to 1.00% base + ~0.15% voter debt (~$2,136/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:
- 828 sq ft (0.02 ac)
- Assessor use:
- Single Family Attached
- Addresses on lot:
- 83 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: $1,927,000 – $2,453,000 · 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 130 total building permits recorded within ½ mile.
- New construction1 permit
- Demolition1 permit
- Additions & renovations13 permits
- Building systems88 permits
- Repairs14 permits
- Other13 permits
Developments Deserving Closer Investigation & Active Area Builders
- New home at 218 Meda Ln (Applied)0.47 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)0.34 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)0.41 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)0.46 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: Lamperti Contracting And Design (1 on parcel, 1 in ½ mi · Remodel / interior alteration); Jemico (1 on parcel, 1 in ½ mi · Windows / doors / siding); Pedro Femenia And Sons (1 on parcel, 1 in ½ mi · HVAC / heat pump); Burkell Plumbing (1 on parcel, 1 in ½ mi · Plumbing / water heater / sewer); Owner Builder (8 in ½ mi · Remodel / interior alteration).
Permit & Project History on This Parcel (4 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| 179785 | Remodel / interior alteration | Issued | Iss. Aug 4, 2025 | $120,000 | Remodel Kitchen, Master & Secondary Bathrms; Electrical In Other Areas |
| B41495 | Plumbing / water heater / sewer | Issued | Iss. Mar 11, 2025 | $3,000 | Replace 50 gallon water heater with same in same location — Replace Plumbing Fixtures(s) |
| B36502 | HVAC / heat pump | Issued | Iss. Dec 21, 2023 | $3,990 | Replace the furnace-like for like in the same spot the old furnace was. New Payne 80% efficiency 90K BTU's natural gas f… |
| B35413 | Windows / doors / siding | Issued | Iss. Sep 14, 2023 | $6,214 | Remove & replace 1 retrofit window. — Non-structural Door/Window Replacement |