300 A Morning Sun Ave
Mill Valley 94941 · Tamalpais · Unincorporated Marin · Coordinates: 37.88056, -122.52879
Parcel & Assessor
- Lot size:
- 6,534 sq ft (0.15 ac)
- Assessor use:
- Single-Resid. - Improved
- Addresses on lot:
- 300A MORNING SUN AVE; 300 MORNING SUN AVE
Zoning & Land Use
R1-B1 — Residential Single Family (Unincorporated Marin)
State Housing Pathways Screen (ADU & SB 9)
- ADU or junior ADULikely eligible
Zoned R1-B1 (single-family residential): state law allows ADUs where homes are allowed.
- SB 9: two homes on the lotLikely eligible
Zoned R1-B1, a single-family residential zone.
- SB 9: split into two lotsLikely eligible
Zoned R1-B1, a single-family residential zone. The lot is 6,534 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 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: $2,052,000 – $2,612,000 · 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
- Accessory dwelling unit at 300 Morning Sun Ave (adu 300a) (Issued)On this parcel
Active in "Issued" for 2.6 yr (first record Apr 2, 2024) with no new permit activity recorded in 19 mo.
- New home at 217 Cleveland Ave (Issued)0.31 mi N
Active in "Issued" for 9.7 yr (first record Feb 21, 2017) with no new permit activity recorded in 2.3 yr. High-impact scale (1 housing unit, $875,000 declared valuation across 1 permit).
- Accessory dwelling unit at 403 Marin Ave (adu 403a) (Issued)0.42 mi SW
Active in "Issued" for 2.9 yr (first record Dec 21, 2023) with no new permit activity recorded in 18 mo. High-impact scale (1 housing unit, $1,000,000 declared valuation across 1 permit).
- New home at 290 Greene St (Issued)250 ft N
Active in "Issued" for 3.2 yr (first record Aug 14, 2023) with no new permit activity recorded in 3.2 yr.
Permit & Project History on This Parcel (3 permits, 1 grouped projects)
| Record # | Category | Status | Applied / Issued | Valuation | Description |
|---|---|---|---|---|---|
| 178894 | Accessory dwelling unit (new or conversion) | Issued | Iss. Mar 25, 2025 | $400,000 | Remodel; Addition; Attached A D U; Deck |
| 178893 | New garage / accessory structure | Issued | Iss. Mar 25, 2025 | $100,000 | Garage |
| 145192 | Solar / battery storage | Issued | Iss. Dec 10, 2014 | $6,000 | Rooftop Pv 2.75 Kw- Express |
State HCD Housing Element APR records on this parcel: 1 entry (report years 2025).