508 Oceana Dr
Dillon Beach 94929 · Dillon Beach · Unincorporated Marin · Coordinates: 38.25918, -122.96283
Executive Verdict · Public-Records Synthesis
Zoned C-R1 in Unincorporated Marin with likely ADU & SB 9 infill eligibility and mapped CAL FIRE moderate fire hazard severity zone (state responsibility area) due diligence; benchmark value $1,535,000 ($1,351,000–$1,719,000).
Upsides & Opportunities
- ✓ ADU & SB 9 infill pathways screen as likely eligible
Zoned C-R1 supports ministerial ADU/JADU review plus SB 9 both two-unit development and ministerial urban lot split on a 14,636 sq ft lot. Local precedent is active with 2 ADU permits within ¼ mile over the last 36 months.
Source: Unincorporated Marin zoning · CA Gov. Code 66314 & 65852.21
- ✓ Documented permitted upgrades (+$15,040 contributory est.)
Public building records show issued construction/renovation work on this parcel (7 total permits, latest Apr 7, 2025).
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)
- ! CAL FIRE Moderate Fire Hazard Severity Zone (State Responsibility Area) (all of the lot of lot)
Located in a mapped Fire Hazard Severity Zone. Expect Chapter 7A ignition-resistant building standards, defensible-space inspections, and stricter property insurance underwriting.
Source: CAL FIRE FHSZ (map Apr 1, 2024)
- ! Delayed or open permit activity on this parcel
General repair (74273): Pending in review for 11.4 yr (50.3× the 83d median) — slower than 90% of general repair permits in Unincorporated Marin (median 83d, 90th pct 328d, n=693).
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 at 34 Kona Ln (0.15 mi SW, 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)
Parcel & Assessor
- Lot size:
- 14,636 sq ft (0.34 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 508 OCEANA DR
Zoning & Land Use
C-R1 — Residential Single Family (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned C-R1 (single-family residential): state law allows ADUs where homes are allowed.
- SB 9: two homes on the lotLikely eligible
Zoned C-R1, a single-family residential zone.
- SB 9: split into two lotsLikely eligible
Zoned C-R1, a single-family residential zone. The lot is 14,636 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
- Moderate Fire Hazard Severity Zone (State Responsibility Area) (all of the lot, map Apr 1, 2024)
- FEMA National Flood Hazard Layer
- Zone X: minimal flood hazard (all of the lot) · FIRM panel 06041C0040E, effective August 15, 2017
- CGS Alquist-Priolo Earthquake Fault Zone
- Not in an Alquist-Priolo Earthquake Fault Zone
Surrounding Rent & Value Benchmarks (Public Records)
Range: $1,351,000 – $1,719,000 · Status: Off market
HUD Small Area FMR (ZIP 94929) · FY 2026
Studio $2,050 · 1BR $2,510 · 2BR $2,990 · 3BR $4,010 · 4BR $4,280
Developments Deserving Closer Investigation & Active Area Builders
- New home at 34 Kona Ln (Applied)0.15 mi SW
In "Applied" for 3.9 yr (since Dec 27, 2022), 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, $1,000,000 declared valuation across 1 permit).
- General repair (74273) (Applied)On this parcel
Pending in review for 11.4 yr (50.3× the 83d median) — slower than 90% of general repair permits in Unincorporated Marin (median 83d, 90th pct 328d, n=693).
- New home at 429 Oceana Dr (Issued)0.28 mi S
Active in "Issued" for 4 yr (first record Nov 29, 2022) with no new permit activity recorded in 2.3 yr. High-impact scale (1 housing unit, $1,000,000 declared valuation across 1 permit).
- New home at 314 Oceana Dr (Issued)0.38 mi SW
Active in "Issued" for 3.4 yr (first record Jun 6, 2023) with no new permit activity recorded in 2.1 yr. High-impact scale (1 housing unit, $1,783,932 declared valuation across 1 permit).
Entity-resolved builders & contractors in ½ mile: Owner Builder (2 on parcel, 12 in ½ mi · Remodel / interior alteration); Semper Solaris Construction (2 on parcel, 2 in ½ mi · Roof replacement); North Bay Sunspace (1 on parcel, 1 in ½ mi · New garage / accessory structure); Sunrun Installation Services (1 on parcel, 1 in ½ mi · Solar / battery storage); Owner (8 in ½ mi · New garage / accessory structure).
Permit & Project History on This Parcel (7 permits, 0 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| B41888 | Roof replacement | Issued | Iss. Apr 7, 2025 | $24,900 | Remove & dispose off existing roofing material, install new roof, re-flash pipes, vent to code — ReRoofing |
| B41871 | Solar / battery storage | Issued | Iss. Apr 3, 2025 | $2,400 | THIS INSTALLATION INCLUDES THE UNINSTALL & REINSTALL OF (08) EXISTING JA SOLAR JAM54S31-400-MR(400W) SOLAR MODULES DUE T… |
| B37106 | Solar / battery storage | Issued | Iss. Feb 22, 2024 | $11,080 | PV SOLAR 3200 DC, (8) MODULES,(1) 9.8KWh ESS |
| 175716 | New garage / accessory structure | Issued | Iss. Jan 8, 2024 | $29,980 | Enclose Deck For (N) Sunroom W/ Misc Electrical Work |
| 162595 | Windows / doors / siding |