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438 21St Ave

Central Richmond, SF 94121 1524032 2 units · 4 fl · 2005

This building has a higher-than-average number of open problems nearby. Few open issues; problems get fixed quickly. A reasonable bet for a smooth tenancy.

NOVs (7y) vs. neighborhood
Compared to a typical building in Central Richmond
At or below average
avg 0.5
0
FewerMore

This building has 0 novs (7y), at or below the Central Richmond average of 0.5.

Rent & eviction protection

Is 438 21St 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 2005
2 or more units
2 units
Property type
Multi-Family Residential
Zoning
RH2
Not rent-controlled. Buildings constructed after 1978 are generally exempt from SF rent increase limits under the Costa-Hawkins Act.

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

Building characteristics
Units2
Floors4
Year built2005
Total area4,036 sq ft
Property typeMulti-Family Residential
Tax statusHome Owners
Blocklot1524032
Ownership

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

Owner name
Yip/Tang Family Trust
Mailing address
Sze Hoi Yip & Ziling Tang, 438A 21St Ave San Francisco CA 94121
Last sale
122905

Landlord portfolio

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

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Augrented Insights
Initial analysis

The property at 438 21st Avenue in the Central Richmond neighborhood is a four-story, two-unit multi-family residential building constructed in 2005, replacing a three-story single-family dwelling. The development process included significant safety improvements, with the installation of a comprehensive sprinkler system ($14,000) in 2004, though this work prompted an active plumbing complaint for proceeding without proper permits. The building features substantial electrical infrastructure, including 88 lights, 47 switches, 85 receptacles, and 62 circuits, as documented in a permit from February 2004.

Recent activity at the property has primarily involved parking-related issues, with multiple citations issued between 2021 and 2025 for driveway blocking violations. There have been recurring concerns about sidewalk conditions near the property, with documented issues in 2013-2015 regarding a sunken utility vault that affected the sidewalk infrastructure. Historical records show various improvements made in the 1990s, including foundation bolting, kitchen renovations, and restroom additions. The building's construction and subsequent development followed all necessary planning approvals in the RH-2 (Residential, House, Two-Family) District, with the demolition and new construction permits properly processed through the Planning Department.

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

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Risk rating

How 438 21St 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
90th percentile

Out of 2250 buildings in this neighborhood, 225 are predicted to be safer.

RiskiestSafest
Predicted 12-month outcome
91%
No DBI
violation
9%
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.

Permit rate, owner's portfolio

Per-building permit rate across the owner's portfolio.

Number of floors

Building height affects maintenance complexity and is one of the size signals the model uses.

Property class: multi-family flat

2–4 unit flats (class F) are a common SF building type with their own maintenance and complaint patterns.

12-Month severity forecast
No violation 87.6%
Moderate concern 9.2%
Severe concern 3.3%
Estimated probability of receiving a DBI Notice of Violation in the next 12 months at each severity level. Model: full_hgb_balanced.
Apartment reviews

438 21St Ave apartment reviews

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The story over time

438 21St Ave event timeline

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

2023
311 Request Aug 12
Blocking driveway cite only
White - Toyota prius - 8ddm996
311 RequestMar 10
Blocking driveway cite only

See all 2 events

Full history back to 2023 — violations, complaints, permits, buyouts, and fire incidents.

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Every record we have

Full data for 438 21St 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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