148 Great Circle Dr
Mill Valley 94941 · Strawberry · Unincorporated Marin · Coordinates: 37.88179, -122.49996
Executive Verdict · Public-Records Synthesis
Zoned RSP-5 in Unincorporated Marin with likely ADU & SB 9 infill eligibility and zero mapped flood, fire, or fault hazard overlaps; benchmark value $2,396,000 ($2,108,000–$2,684,000).
Upsides & Opportunities
- ✓ ADU & SB 9 infill pathways screen as likely eligible
Zoned RSP-5 supports ministerial ADU/JADU review plus SB 9 both two-unit development and ministerial urban lot split on a 19,733 sq ft lot.
Source: Unincorporated Marin zoning · CA Gov. Code 66314 & 65852.21
- ✓ Documented permitted upgrades (+$65,965 contributory est.)
Public building records show issued construction/renovation work on this parcel (9 total permits, latest Jan 13, 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)
- ! Delayed or open permit activity on this parcel
New garage / accessory structure (77121): Pending in review for 10.7 yr (23.7× the 164d median) — slower than 90% of new garage / accessory structure permits in Unincorporated Marin (median 164d, 90th pct 485d, n=356).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (review-time benchmark)
- ! 5 slow or stalled nearby projects within ½ mile
Closest lead: New home (320 ft W, entitled). 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 (~$28,004/yr at $2,396,000)
Sale triggers reassessment to 1.00% base + ~0.15% voter debt (~$2,334/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:
- 19,733 sq ft (0.45 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 148 GREAT CIRCLE DR
Zoning & Land Use
RSP-5 — Residential Single Family Planned (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned RSP-5 (single-family residential): state law allows ADUs where homes are allowed.
- SB 9: two homes on the lotLikely eligible
Zoned RSP-5, a single-family residential zone.
- SB 9: split into two lotsLikely eligible
Zoned RSP-5, a single-family residential zone. The lot is 19,733 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 06041C0488E, 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: $2,108,000 – $2,684,000 · 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
- New garage / accessory structure (77121) (Applied)On this parcel
Pending in review for 10.7 yr (23.7× the 164d median) — slower than 90% of new garage / accessory structure permits in Unincorporated Marin (median 164d, 90th pct 485d, n=356).
- New home (Entitled)320 ft W
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).
- Demolition at 171 Great Cir Dr (Applied)490 ft NW
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).
- Demolition at 129 Great Cir Dr (Issued)380 ft S
Active in "Issued" for 6.6 yr (first record Apr 1, 2020) with no new permit activity recorded in 6.5 yr.
Entity-resolved builders & contractors in ½ mile: Kerr Construction (2 on parcel, 6 in ½ mi · New garage / accessory structure); Sunrun Installation Services (1 on parcel, 1 in ½ mi · Solar / battery storage); Golden Gate Home Improvement (1 on parcel, 1 in ½ mi · Electrical / panel); Gene Burch Plumbing (1 on parcel, 1 in ½ mi · HVAC / heat pump); Integrity Electric (1 on parcel, 1 in ½ mi · Electrical / panel).
Permit & Project History on This Parcel (9 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| B40821 | Solar / battery storage | Issued | Iss. Jan 13, 2025 | $33,854 | PV SOLAR 12555W DC, 9600W AC, (31) MODULES, (2) 10 KWh ESS |
| B40543 | Electrical / panel | Issued | Iss. Dec 13, 2024 | $1,800 | Replace existing 125 amp main panel underground with new 125 amp main panel — Service Upgrade |
| 170395 | Remodel / interior alteration | Issued | Iss. Jan 14, 2022 | $70,000 | Replace (E) Interior Staircase |
| 165945 | Addition (adds square footage) | Issued | Iss. Oct 12, 2020 | $32,600 | Struct Rmdl Mstr Bth, Addtn, Skylights T.D. 5-5-20 |
| 163466 | HVAC / heat pump | Issued | Iss. Dec 9, 2019 |