San Anselmo 94960 · Sleepy Hollow · APN 177-031-22 · Unincorporated Marin
Since October 2024 within ½ mile: 1 homes completed, 2 permitted, 1 proposed or in review.
4 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.
192 permits within ½ mile since October 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.
$1,973,000
Benchmark range: $1,736,000 – $2,210,000
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Geography: permits located by parcel, ½ mile radius · Retrieved Oct 29, 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 Oct 29, 2026) · CAL FIRE Office of the State Fire Marshal, Fire Hazard Severity Zones in the State Responsibility Area (effective 2024-04-01) (retrieved Oct 26, 2026) · CAL FIRE Office of the State Fire Marshal, Fire Hazard Severity Zones in the Local Responsibility Area (map dated 2025-03-24) (retrieved Oct 26, 2026) · FEMA, National Flood Hazard Layer — flood hazard zones (retrieved Oct 26, 2026) · FEMA, National Flood Hazard Layer — FIRM panels (retrieved Oct 26, 2026) · California Geological Survey, Alquist-Priolo Earthquake Fault Zones (retrieved Oct 26, 2026) · Zoning classes: our classification of R1-BD 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.
Permit issued and active for 6.7 yr (first record Feb 7, 2020), with no completion or new permit record in 6.7 yr. · 1 unit
Permit issued and active for 12.8 yr (first record Dec 24, 2013), with no completion or new permit record in 12.4 yr. · 1 unit · $800,000 declared valuation
Permit issued and active for 10.2 yr (first record Aug 23, 2016), with no completion or new permit record in 10.1 yr. · $10,000 declared valuation
Permit issued and active for 8.2 yr (first record Aug 9, 2018), with no completion or new permit record in 7.5 yr. · 1 unit · $1,097,000 declared valuation
In "Applied" for 7.5 yr (since Apr 29, 2019), with no new permit record in 7.5 yr. · 1 unit · $1,000,000 declared valuation
Permit issued and active for 7.7 yr (first record Feb 21, 2019), with no completion or new permit record in 7.5 yr. · 1 unit · $35,000 declared valuation
Nearby electrical / panel (150 W Oak Knoll Dr): First appeared in published agency feed
Record B48927 · Detected between snapshots
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Snapshot diff within ½ mile
Nearby other (111 Deer Hollow Rd): First appeared in published agency feed
Record B48924 · 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)
45 Oak Knoll Dr · 1 unit · $100,000 valuation
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 $1,657,204 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)
1 unit
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) & HCD APR (grouped project within ½ mile)
196 Deer Hollow Rd (Adu 196a) · 1 unit · $150,000 valuation
Records span Sep 6, 2024 to Aug 28, 2025 (1 permit).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) & HCD APR (grouped project within ½ mile)
33 Fawn Dr · 1 unit · $900,000 valuation
Records span Sep 1, 2023 to Oct 7, 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)
854 Butterfield Ln · $500 valuation
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) & HCD APR (grouped project within ½ mile)
Roof replacement permit issued (B36204)
Recorded status: Issued
Tear off and replacement like for like comp shingles class A fire rated shingles. full home reroof 35sqs — ReRoofing · Declared valuation: $22,600 · Contractor: Green Hill Roofing Inc
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Geography: parcel
Roof replacement permit application filed (B36204)
Current status: Issued
Tear off and replacement like for like comp shingles class A fire rated shingles. full home reroof 35sqs — ReRoofing · Declared valuation: $22,600 · Contractor: Green Hill Roofing Inc
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Geography: parcel
107 Deer Hollow Rd (Aka 107a) · 1 unit · $80,000 valuation
Records span Jul 19, 2023 to Nov 14, 2023 (1 permit).
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) & HCD APR (grouped project within ½ mile)
Solar / battery storage permit application filed (B36032)
Current status: Issued
PV on roof 17.94kW DC 15.2kW AC 46 mods (n) 13.5KWh ESS (n) 125A sub · Declared valuation: $42,086 · Contractor: Sunrun Installation Services Inc
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Geography: parcel
Solar / battery storage permit issued (B36032)
Recorded status: Issued
PV on roof 17.94kW DC 15.2kW AC 46 mods (n) 13.5KWh ESS (n) 125A sub · Declared valuation: $42,086 · Contractor: Sunrun Installation Services 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 →Active in "Issued" for 6.7 yr (first record Feb 7, 2020) with no new permit activity recorded in 6.7 yr.
Active in "Issued" for 8.2 yr (first record Aug 9, 2018) with no new permit activity recorded in 7.5 yr. High-impact scale (1 housing unit, $1,097,000 declared valuation across 2 permits).
Active in "Applied" for 7.5 yr (first record Apr 29, 2019) with no new permit activity recorded in 7.5 yr. High-impact scale (1 housing unit, $1,000,000 declared valuation across 1 permit).
Active in "Issued" for 12.8 yr (first record Dec 24, 2013) with no new permit activity recorded in 12.4 yr. High-impact scale (1 housing unit, $800,000 declared valuation across 1 permit).
Active in "Applied" for 2.2 yr (first record Aug 1, 2024) with no new permit activity recorded in 2.2 yr.
Active in "Issued" for 7.5 yr (first record May 16, 2019) with no new permit activity recorded in 7 yr.
Substantial improvements (additions, interior remodels, ADUs, commercial TI, and new builds) across 980 parcels
+0.0% YoY
City baseline: 16.5 / 1k
32 in trailing 24m
Includes 6 ADUs
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 ($19,750/yr) + local voter-approved bond debt ($2,963/yr) + fixed direct levies/Mello-Roos ($450/yr).
Mapped hazard zone insurance context on this parcel:
−$112,401/yr
Cash needed: $434,500
NOI: $7,439/yr
P&I: $9,987/mo
For $0/mo net cash flow
At $3,650/mo 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 | −$9,786/mo | -27.0% | $17,018/mo | −$9,823/mo |
| Base (your inputs) | Your entered assumptions, 3.0%/yr rent growth | $3,650/mo | −$9,367/mo | -25.9% | $15,752/mo | −$9,197/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 | −$9,126/mo | -25.2% | $15,386/mo | −$8,720/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.
Issued1 unitsFeb 7, 2020 – Feb 7, 2020
We group related permits and State housing reports into projects. That grouping is our inference, not an official record.
Tear off and replacement like for like comp shingles class A fire rated shingles. full home reroof 35sqs — ReRoofing
PV on roof 17.94kW DC 15.2kW AC 46 mods (n) 13.5KWh ESS (n) 125A sub
Conv. Lvg Space To Jadu
Conv. Garage To Lvg Space, Struct. Rmdl T.D. 10/28/19
Pergola T.D. 9/18/19
Source: County of Marin Community Development Agency, Building Permits (unincorporated Marin) · Geography: parcel (APN) · Retrieved Oct 29, 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.
| Report year | Project / record | Type | Entitled | Permitted | Completed | Deed-restricted |
|---|---|---|---|---|---|---|
| 2020 | — | ADU · Renter | — | 1 (Feb 7, 2020) | — | — |
Source: California HCD, Housing Element Annual Progress Report — Table A2 · Geography: project (parcel) · Retrieved Oct 26, 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 Oct 29, 2026
0.37 acres
Assessor's classification for assessment purposes. This is not zoning.
880 BUTTERFIELD RD
Source: County of Marin GIS (MarinMap), Parcels · Geography: parcel · Retrieved Oct 29, 2026
Search by parcel number 177-031-22. Assessed value is not market value.
Search by parcel number 177-031-22 (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.