San Anselmo 94960 · Sleepy Hollow · APN 176-251-16 · Unincorporated Marin
Zoned RSP-0.25 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 $1,792,000 ($1,577,000–$2,007,000).
Zoned RSP-0.25 supports ministerial ADU/JADU review plus SB 9 both two-unit development and ministerial urban lot split on a 224,160 sq ft lot. Local precedent is active with 3 ADU permits within ¼ mile over the last 36 months.
Source: Unincorporated Marin zoning · CA Gov. Code 66314 & 65852.21
On-parcel permit history is indexed through Nov 6, 2025, letting you verify roof, HVAC, electrical, or structural work against seller disclosures.
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (parcel APN)
32 substantial renovation & housing permits over 24 months (32.7 per 1,000 parcels vs. 16.3 citywide baseline) (#4 of 22 neighborhoods).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) (Sleepy Hollow)
Automated synthesis of indexed municipal, county, state, and federal public records — informational context only, not a formal appraisal, survey, or legal/tax determination.
$1,792,000
Benchmark range: $1,577,000 – $2,007,000
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)
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)
Closest lead: New home at 99 Garden Rock Rd (0.16 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)
Sale triggers reassessment to 1.00% base + ~0.15% voter debt (~$1,755/mo). Confirm exact Mello-Roos / CFD special assessments on the county tax bill.
Source: CA Const. Art. XIIIA (Prop 13) · County Tax Collector
Since November 2024 within ½ mile: 1 permitted.
1 projects with a record in this window, grouped by us from permits and State housing reports. Units are as proposed on each project's latest record and counted at its current stage.
139 permits within ½ mile since November 2024
The map shows new construction, ADUs, demolitions, additions, and renovations. Routine systems work (roofs, HVAC, water heaters) is counted but not mapped. Unit counts are as stated on permits.
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Geography: permits located by parcel, ½ mile radius · Retrieved Nov 14, 2026
Public-records benchmark estimate combining Zillow Home Value Index (Data provided by Zillow), Census ACS 5-year estimates, parcel land-use/lot characteristics, and issued building permits. Not an official appraisal.
Permit counts, by the date issued (or applied, if not yet issued). Lot splits are planning cases, which we don't have.
We read public zoning and hazard maps against state law (ADUs: Gov. Code 66314; SB 9: Gov. Code 65852.21 and 66411.7). Local rules, title, tenancy history and site conditions can change the answer. Check with Unincorporated Marin's planning department before relying on it.
Sources: County of Marin GIS (MarinMap), Zoning (11 cities and unincorporated Marin) (retrieved Nov 14, 2026) · CAL FIRE Office of the State Fire Marshal, Fire Hazard Severity Zones in the State Responsibility Area (effective 2024-04-01) (retrieved Nov 9, 2026) · CAL FIRE Office of the State Fire Marshal, Fire Hazard Severity Zones in the Local Responsibility Area (map dated 2025-03-24) (retrieved Nov 9, 2026) · FEMA, National Flood Hazard Layer — flood hazard zones (retrieved Nov 9, 2026) · FEMA, National Flood Hazard Layer — FIRM panels (retrieved Nov 9, 2026) · California Geological Survey, Alquist-Priolo Earthquake Fault Zones (retrieved Nov 9, 2026) · Zoning classes: our classification of RSP-0.25 as single-family residential, checked against the zone description on Oct 24, 2026
Chronological history of building permit applications and issuances, snapshot-dated status changes, State housing entitlements, surrounding development within ½ mile, and area home-value trends.
In "Applied" for 12.2 yr (since Aug 28, 2014), with no new permit record in 12.2 yr. · $15,000 declared valuation
Permit issued and active for 10.9 yr (first record Dec 23, 2015), with no completion or new permit record in 10.6 yr. · 1 unit · $615,000 declared valuation
Permit issued and active for 7.4 yr (first record Jun 27, 2019), with no completion or new permit record in 6.8 yr. · 1 unit · $175,000 declared valuation
In "Applied" for 5.4 yr (since Jun 8, 2021), with no new permit record in 5.4 yr. · 1 unit · $15,000 declared valuation
In "Applied" for 4.6 yr (since Mar 31, 2022), with no new permit record in 4.6 yr. · 1 unit · $196,000 declared valuation
Permit issued and active for 3.6 yr (first record Apr 5, 2023), with no completion or new permit record in 3.3 yr. · 1 unit · $292,000 declared valuation
Nearby other (103 Van Winkle Dr): First appeared in published agency feed
Record 94647 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Nearby windows / doors / siding (100 Crane Dr): First appeared in published agency feed
Record B49067 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Nearby roof replacement (16 Dutch Valley Ln): First appeared in published agency feed
Record B49029 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Nearby addition (adds square footage) (15 Estates Dr): Contractor changed from STEVE REMPE GENERAL CONTRACTOR INC to REMPE CONSTRUCTION
Record 182713 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Nearby electrical / panel (185 Van Winkle Dr): First appeared in published agency feed
Record B48979 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Nearby plumbing / water heater / sewer (5 Dutch Valley Ln): First appeared in published agency feed
Record B48882 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Latest published Zillow Home Value Index (ZHVI) update
Changed from $1,602,637 in September 2025 to $1,702,818 in September 2026.
Source: Zillow Home Value Index (ZHVI) · Data provided by Zillow · Geography: ZIP 94960 (not a parcel appraisal)
Plumbing / water heater / sewer permit application filed (B44698)
Current status: Issued
INSTALL TANKLESS WATER HEATER WITH 199K BTUS — Replace Plumbing Fixtures(s) · Declared valuation: $3,700 · Contractor: Gagne Brothers Enterprises Inc
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Geography: parcel
Plumbing / water heater / sewer permit issued (B44698)
Recorded status: Issued
INSTALL TANKLESS WATER HEATER WITH 199K BTUS — Replace Plumbing Fixtures(s) · Declared valuation: $3,700 · Contractor: Gagne Brothers Enterprises Inc
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Geography: parcel
Annual ZIP 94960 home-value index checkpoint
Changed from $1,657,204 in September 2024 to $1,602,637 in September 2025.
Source: Zillow Home Value Index (ZHVI) · Data provided by Zillow · Geography: ZIP 94960 (not a parcel appraisal)
135 Tarry Rd (Aka 135 A) · 1 unit · $325,000 valuation
Records span Aug 13, 2024 to Apr 2, 2025 (1 permit).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) & HCD APR (grouped project within ½ mile)
125 Tarry Rd (Adu 125a) · 1 unit · $40,000 valuation
Records span Mar 28, 2024 to Oct 21, 2024 (1 permit).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) & HCD APR (grouped project within ½ mile)
Annual ZIP 94960 home-value index checkpoint
Changed from $1,652,687 in September 2023 to $1,657,204 in September 2024.
Source: Zillow Home Value Index (ZHVI) · Data provided by Zillow · Geography: ZIP 94960 (not a parcel appraisal)
60 Tarry Rd (Aka 60 A) · 1 unit · $391,060 valuation
Records span Jun 9, 2023 to Dec 7, 2023 (1 permit).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) & HCD APR (grouped project within ½ mile)
HVAC / heat pump permit application filed (B35880)
Current status: Issued
Replace ductwork in attic and crawlspace. 7 runs in attic and 11 in crawlspace. — Replace Ductwork · Declared valuation: $20,000 · Contractor: Peter Levi Plumbing Inc
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Geography: parcel
Cross-referenced intelligence from our historical development graph—connecting parcels, permits, entity-resolved builders, empirical review-time distributions, and neighborhood renovation trends.
Explore full Unincorporated Marin development graph →In "Applied" for 3.1 yr (since Oct 11, 2023), 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, $1,200,000 declared valuation across 1 permit).
In "Applied" for 12.2 yr (since Aug 28, 2014), exceeding the 55d median and 261d 90th percentile for demolition permits in Unincorporated Marin (n=130).
In "Applied" for 4.6 yr (since Mar 31, 2022), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121).
In "Applied" for 5.4 yr (since Jun 8, 2021), exceeding the 253d median and 686d 90th percentile for new single-family home permits in Unincorporated Marin (n=121).
Active in "Issued" for 2.6 yr (first record Mar 28, 2024) with no new permit activity recorded in 2.1 yr.
Active in "Issued" for 2.3 yr (first record Aug 13, 2024) with no new permit activity recorded in 19 mo.
Substantial improvements (additions, interior remodels, ADUs, commercial TI, and new builds) across 980 parcels
−11.8% YoY
City baseline: 16.3 / 1k
32 in trailing 24m
Includes 5 ADUs
| Builder / contractor | Primary specialty | Here / ½ mi | ½ mi valuation | Citywide 24m trend |
|---|---|---|---|---|
| Peter Levi Plumbing | HVAC / heat pump | 2 on parcel2 in ½ mi | $43,861 | 0 vs 0 prior |
| Ground Up Construction Development | Roof replacement | 1 on parcel1 in ½ mi | $7,500 | 0 vs 0 prior |
| Preferred Plumbing And Drain | Plumbing / water heater / sewer | 1 on parcel1 in ½ mi | $7,200 |
| Permit category | Sample (n) | 25th pct | Median (50th) | 75th pct | 90th pct | Recent 24m median |
|---|---|---|---|---|---|---|
| New single-family home | 121 | 166d | 253d | 456d | 686d | 210d(vs 276d prior) |
| New multifamily / condos / mixed-use | 21 | 272d | 292d | 293d | 313d | 293d(vs 197d prior) |
| Accessory dwelling unit (new or conversion) | 298 | 120d | 204d | 331d | 549d | 214d(vs 181d prior) |
| Addition (adds square footage) |
HUD Small Area Fair Market Rent · ZIP 94960
HUD FY 2026 · 40th-percentile gross rentCensus ACS 5-year median gross rent (all bedroom counts combined):
Area home-value benchmarks (not an appraisal)
ZIP & neighborhood mediansUnder California Proposition 13, the seller's historical assessed value does not carry over to a buyer. On sale, the parcel is reassessed at the purchase price: 1.00% base rate ($17,900/yr) + local voter-approved bond debt ($2,685/yr) + fixed direct levies/Mello-Roos ($450/yr).
Mapped hazard zone insurance context on this parcel:
Model adding a backyard ADU or garage conversion under California's Prop 13 blended new-construction assessment (existing house & land tax base stays intact; only ADU build cost is assessed) and SB 13 impact-fee rules.
−$99,048/yr
Cash needed: $393,800
NOI: $9,566/yr
P&I: $9,051/mo
For $0/mo net cash flow
At $3,650/mo gross rent
| Scenario | Assumptions | Year 1 Rent | Year 1 Cash Flow | Cash-on-Cash | Break-Even Rent | Year 5 Cash Flow |
|---|---|---|---|---|---|---|
| Conservative | −8% starting rent, +3% vacancy, +3% combined maintenance/CapEx, 1.5%/yr rent growth | $3,358/mo | −$8,673/mo | -26.4% | $15,465/mo | −$8,696/mo |
| Base (your inputs) | Your entered assumptions, 3.0%/yr rent growth | $3,650/mo | −$8,254/mo | -25.2% | $14,314/mo | −$8,069/mo |
| Optimistic (cap-limited) | +6% starting rent, 3% vacancy, 4.5%/yr rent growth (capped by AB 1482 ceiling of 8.6%/yr) | $3,869/mo | −$8,013/mo | -24.4% | $13,982/mo | −$7,593/mo |
Rental regulatory context (informational only — not legal advice):
California AB 1482 (Tenant Protection Act, Civ. Code § 1947.12) caps annual rent increases at 5% + local CPI (max 10%) on covered properties.
INSTALL TANKLESS WATER HEATER WITH 199K BTUS — Replace Plumbing Fixtures(s)
Replace ductwork in attic and crawlspace. 7 runs in attic and 11 in crawlspace. — Replace Ductwork
Replacement of Gas line — New Gas Service, Replace Plumbing Fixtures(s)
Remove and replace aprox 14500 sq ft of roofing material. — ReRoofing
Repl Heater
Replace Water Line From Meter To House
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Geography: parcel (APN) · Retrieved Nov 14, 2026 · Received and issued dates come from the County of Marin. The county publishes no final or expired status, so an issued permit stays 'Issued' after the work is done.
No housing activity reported to the State for this parcel (2018–2025 reports).
Source: California HCD, Housing Element Annual Progress Report — Table A2 · Geography: project (parcel) · Retrieved Nov 9, 2026 · From Unincorporated Marin's Housing Element Annual Progress Reports. A project can appear in several report years as it moves from entitlement to permit to completion.
Source: County of Marin GIS (MarinMap), Zoning (11 cities and unincorporated Marin) · Geography: zoning district polygon at parcel point · Retrieved Nov 14, 2026
5.15 acres
Assessor's classification for assessment purposes. This is not zoning.
1 SULPHUR SPA RD
Source: County of Marin GIS (MarinMap), Parcels · Geography: parcel · Retrieved Nov 14, 2026
Search by parcel number 176-251-16. Assessed value is not market value.
Search by parcel number 176-251-16 (Marin County Tax Collector)
Permits issued in unincorporated Marin in the past 48 months. Each city keeps its own records.
The official flood hazard map for this location. Our reading of it is under What could be built here.
This site does not show owner names.
| 0 vs 0 prior |
| Gagne Brothers Enterprises | Plumbing / water heater / sewer | 1 on parcel1 in ½ mi | $3,700 | 0 vs 0 prior |
| Eco Heating And Air | HVAC / heat pump | 1 on parcel1 in ½ mi | $1,850 | 0 vs 0 prior |
| Owner Builder Recent nearby: 4 Whiteplains Ct (Jun 23, 2023) | Remodel / interior alteration | 12 in ½ mi | $1,954,500 | 226 vs 240 prior−6% |
| Owner Recent nearby: 6 Crane Dr (Feb 7, 2022) | New garage / accessory structure | 9 in ½ mi | $364,500 | 25 vs 15 prior+67% |
| Cedar House Construction Recent nearby: 175 Van Winkle Dr (May 19, 2020) | New garage / accessory structure | 6 in ½ mi | $294,200 | 0 vs 0 prior |
| Dotto Construction Recent nearby: 125 Tarry Rd (Dec 4, 2024) | Remodel / interior alteration | 4 in ½ mi | $950,000 | 1 vs 9 prior−89% |
| Levine Design And Construction Recent nearby: 145 Crane Dr (May 16, 2016) | New garage / accessory structure | 4 in ½ mi | $760,000 | 1 vs 4 prior |
| 316 |
| 103d |
| 160d |
| 249d |
| 440d |
| 159d(vs 166d prior) |
| Remodel / interior alteration | 1,054 | 36d | 83d | 148d | 266d | 112d(vs 77d prior) |
| Commercial tenant improvement | 81 | 99d | 148d | 233d | 443d | 152d(vs 150d prior) |
| Roof replacementOn this parcel | 3,663 | 0d | 0d | 0d | 0d | 0d |
| HVAC / heat pumpOn this parcel | 2,946 | 0d | 0d | 0d | 0d | 0d |
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Computed from issued permits with recorded application and issuance dates over the trailing 60 months. Categories with fewer than 20 permits are excluded.