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664-666 9Th Ave

Inner Richmond, SF 94118 1636015 5 units · 2 fl · 1909

This building has significantly more problems than most nearby buildings. Few open issues; problems get fixed quickly. A reasonable bet for a smooth tenancy.

NOVs (7y) vs. neighborhood
Compared to a typical building in Inner Richmond
Above average
avg 0.9
1
FewerMore

This building has 1 novs (7y), above the Inner Richmond average of 0.9.

Rent & eviction protection

Is 664-666 9Th Ave rent-controlled?

San Francisco's Rent Ordinance caps rent increases and provides eviction protection for most residential units built before 1979 with 2+ units. Here's how this building scores.

Built before 1979
Built 1909
2 or more units
5 units
Property type
Multi-Family Residential
Zoning
RH2
Likely rent-controlled. Building age and unit count suggest this property falls under San Francisco's Rent Ordinance.

Based on SF Assessor records. Not legal advice — confirm with the SF Rent Board.

Building characteristics
Units5
Floors2
Year built1909
Total area5,295 sq ft
Property typeMulti-Family Residential
Tax statusNone
Blocklot1636015
Ownership

Registered owner per SF Assessor-Recorder (secured roll).

Owner name
Wellington H Trinh Trust
Mailing address
2050 Quesada Ave San Francisco CA 94124
Last sale
060401

Landlord portfolio

Other SF properties this owner holds, with risk grades for each.

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Multiple entrances & addresses

Included addresses

All street addresses sharing this blocklot that are covered by this report.

666 09th Ave, San Francisco, CA 94118
664 09th Ave, San Francisco, CA 94118
Augrented Insights
Initial analysis

The property at 664-666 9th Avenue in the Inner Richmond is a 2-story, 5-unit multi-family residential building constructed in 1909, currently owned by the Wellington H Trinh Trust. The building has experienced several significant maintenance issues and code compliance matters over its history, with the most pressing concerns occurring in the early 2000s when multiple violations were documented in 2000 related to building safety, lead paint hazards, electrical systems, and security features. These issues, which included problems with stairs, lighting, and garbage storage, were all officially abated by August 2005 following several completed permits for improvements, including stairway lighting installation and structural modifications.

More recent concerns have primarily centered around plumbing infrastructure, with the most recent significant work completed in December 2019 involving sewer repairs and trap replacement following a documented problem with a broken house trap. The building underwent a mandatory soft-story retrofit inspection in 2017, which was resolved in early 2018. Routine housing inspections have been conducted regularly over the years, with the most recent ones in 2017 and 2010 showing no active violations. The property has experienced multiple sewer-related issues, particularly in late 2019, as evidenced by several 311 calls regarding sewer backups and flooding problems, though these were ultimately resolved through appropriate maintenance work. The most recent building activity consists of parking enforcement issues documented in 2023 and 2024, which are external matters unrelated to building safety or maintenance.

AI-generated · may contain errors · check the source data tables below

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Risk rating

How 664-666 9Th Ave's risk score is calculated

We trained a model on 7 years of SF DBI inspection data — notice of violation filings, complaint history, and owner track records. It estimates the probability that DBI inspectors will issue a Notice of Violation at this address in the next 12 months. Lower % = safer.

What the score means for you

Grade A–B — Low risk

DBI rarely finds violations here. Strong maintenance history and a clean complaint record.

Grade C — Moderate risk

Some past violations or complaints on record. Worth asking the landlord about any open issues before signing.

Grade D–F — High risk

Elevated violation and complaint history. DBI has found issues here before and is statistically likely to again.

Neighborhood percentile
18th percentile

Out of 1723 buildings in this neighborhood, 1413 are predicted to be safer.

RiskiestSafest
Predicted 12-month outcome
66%
No DBI
violation
34%
DBI violation
likely
Model explanation

What's driving this score

The three data points that most influenced this building's risk rating — ranked by the weight the model placed on each one.

Number of units

The number of units affects how the model reads complaint and violation totals — more units means more potential sources.

DBI tenant complaints (past 7 years)

Formal complaints tenants filed with DBI about this building over 7 years.

Building size

Total floor area — a proxy for building scale and the number of systems (plumbing, electrical, HVAC) that can fail.

12-Month severity forecast
No violation 67.5%
Moderate concern 24.4%
Severe concern 8.1%
Estimated probability of receiving a DBI Notice of Violation in the next 12 months at each severity level. Model: full_hgb_balanced.
Apartment reviews

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The story over time

664-666 9Th Ave event timeline

Violations, complaints, fire incidents, permits, and buyouts — most recent records in order.

2026
311 Request Feb 03
Garbage and debris
other bagged boxed contained garbage
311 RequestFeb 03
Public works

See all 7 events

Full history back to 2019 — violations, complaints, permits, buyouts, and fire incidents.

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Every record we have

Full data for 664-666 9Th Ave apartments

13 SF public datasets for this parcel — permits, violations, complaints, fire records, 311 calls, planning records, and buyouts.

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Cancel anytime · Data sourced from SF Open Data, DBI, SFFD, SF Rent Board & Planning

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