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539-541 21St Ave

Central Richmond, SF 94121 1564007 2 units · 2 fl · 1922

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 539-541 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 1922
2 or more units
2 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
Units2
Floors2
Year built1922
Total area3,290 sq ft
Property typeMulti-Family Residential
Tax statusHome Owners
Blocklot1564007
Ownership

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

Owner name
Ungson Perry & Nancy
Mailing address
541 21st Ave San Francisco CA 94121
Last sale
102518

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.

541 21st Ave, San Francisco, CA 94121
539 21st Ave, San Francisco, CA 94121
Augrented Insights
Initial analysis

The two-unit residential building at 539-541 21st Avenue in the Central Richmond neighborhood, owned by Perry and Nancy Ungson, has undergone several significant renovations and improvements since its construction in 1922. Most notably, recent upgrades include the installation of a solar panel system (3.78kW with 12 panels) and an energy storage system (13.5kWh Powerwall) in 2019-2020, demonstrating commitment to sustainable energy. The property has seen substantial interior improvements over the past decade, including multiple kitchen remodels (most recently in 2018 at a cost of $22,347), bathroom renovations, and the conversion of the ground floor garage into a childcare space in 2016 (costing $60,000) which included comprehensive updates to electrical systems, plumbing, and fixtures.

The building underwent termite repairs in early 2015, addressing issues identified in a report by Lingruen Associates. Earlier renovation work included window replacement, reroofing, and various plumbing and electrical upgrades, including the installation of a new furnace and hot water heater in 2013. The property experienced some regulatory challenges in 2013-2014 related to unpermitted remodeling work, which resulted in violation notices and monitoring fees, though these issues were ultimately resolved and abated by July 2014. Since then, there have been no active building violations or complaints on record.

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

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Risk rating

How 539-541 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
54th percentile

Out of 2250 buildings in this neighborhood, 1035 are predicted to be safer.

RiskiestSafest
Predicted 12-month outcome
85%
No DBI
violation
15%
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.

Construction spend, owner's portfolio

Estimated permit value across all of this owner's buildings.

DBI complaint rate, owner's portfolio

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

Estimated permit spend (past 7 years)

Dollar value of permits pulled at this address — large recent spend can signal deferred-maintenance catch-up.

12-Month severity forecast
No violation 81.7%
Moderate concern 12.3%
Severe concern 6.0%
Estimated probability of receiving a DBI Notice of Violation in the next 12 months at each severity level. Model: full_hgb_balanced.
Apartment reviews

539-541 21St Ave apartment reviews

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The story over time

539-541 21St Ave event timeline

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

2020
Electrical Permit Feb 13
Install energy storage system 13.5kwh (1 powerwall) +125a load center
Complete

See all 2 events

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

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Every record we have

Full data for 539-541 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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