20 Seminary Cove Dr
Mill Valley 94941 · Strawberry · Unincorporated Marin · Coordinates: 37.88430, -122.50757
Executive Verdict · Public-Records Synthesis
Zoned RMP-2.47 in Unincorporated Marin with likely ministerial ADU eligibility and zero mapped flood, fire, or fault hazard overlaps; benchmark value $2,270,000 ($1,998,000–$2,542,000).
Upsides & Opportunities
- ✓ Ministerial ADU / JADU pathway likely eligible
Zone RMP-2.47 allows residential use qualifying for ministerial ADU review under state law.
Source: Unincorporated Marin zoning · CA Gov. Code 66314
- ✓ Documented permitted upgrades (+$147,504 contributory est.)
Public building records show issued construction/renovation work on this parcel (3 total permits, latest Nov 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: Demolition at 171 Great Cir Dr (0.36 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 (~$26,555/yr at $2,270,000)
Sale triggers reassessment to 1.00% base + ~0.15% voter debt (~$2,213/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:
- 5,837 sq ft (0.13 ac)
- Assessor use:
- Single Family Attached
- Addresses on lot:
- 20 SEMINARY COVE DR
Zoning & Land Use
RMP-2.47 — Residential Multiple Planned (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned RMP-2.47 (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-2.47 (multifamily residential), not a single-family residential zone.
- SB 9: split into two lotsUnlikely
Zoned RMP-2.47 (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: $1,998,000 – $2,542,000 · 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
Developments Deserving Closer Investigation & Active Area Builders
- Demolition at 171 Great Cir Dr (Applied)0.36 mi E
In "Applied" for 15 mo (since Aug 14, 2025), exceeding the 55d median and 261d 90th percentile for demolition permits in Unincorporated Marin (n=130).
- New home (Entitled)0.39 mi SE
In "Entitled" for 5.1 yr (since Sep 30, 2021), 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)0.48 mi N
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).
- Demolition at 604 Seminary Dr (Issued)0.22 mi E
Active in "Issued" for 7.3 yr (first record Jul 17, 2019) with no new permit activity recorded in 7.3 yr.
Entity-resolved builders & contractors in ½ mile: Floyd Construction (1 on parcel, 2 in ½ mi · Remodel / interior alteration); Sun Light And Power (1 on parcel, 1 in ½ mi · Solar / battery storage); Kelly Plumbing And Heating (1 on parcel, 1 in ½ mi · HVAC / heat pump); Lek Enterprises (35 in ½ mi · Remodel / interior alteration); Owner (18 in ½ mi · Remodel / interior alteration).
Permit & Project History on This Parcel (3 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| B44665 | Solar / battery storage | Issued | Iss. Nov 4, 2025 | $22,000 | (N) Residential Roof-mount Solar PV, (18) Modules, (8.28) kW (N) Battery Backup, (1) Frankline aPower (15) kWh (N) 125A … |
| B40837 | HVAC / heat pump | Issued | Iss. Jan 13, 2025 | $15,500 | Replace furnace and ac in existing locations and tankless water heater — Replace Plumbing Fixtures(s); Replace Mechanica… |
| 176680 | Remodel / interior alteration | Issued | Iss. May 21, 2024 | $450,000 | Interior Remodel; Add A/C To (E) H V A C System |