Free SF apartment background check

493-499 21St Ave

Central Richmond, SF 94121 1523018 4 units · 2 fl · 1917

A handful of records on file over the last seven years, and our model puts this building at a low risk of further maintenance problems in the next 12 months. A few records worth reading before you sign. Check whether they were closed out, and ask what was actually fixed.

NOVs (7y) vs. neighborhood
Records already on file, against a typical building in Central Richmond — not a forecast
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 493-499 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 1917
2 or more units
4 units
Property type
Multi-Family Residential
Zoning
RM1
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.

Statewide backstop · AB 1482

California Tenant Protection Act of 2019

Even when a building isn't covered by local rent stabilization, the statewide Tenant Protection Act (AB 1482) may still apply. It caps annual rent increases and requires the landlord to state a legal reason to end most tenancies.

15+ years since occupancy
Built 1917
Annual rent increase cap
5% + CPI, max 10%
Just-cause eviction
After 12 months
Local rent control likely takes priority. This building appears to fall under the local ordinance above, which is stronger than AB 1482. Where a local just-cause ordinance applies, its rules govern instead of the state cap.

AB 1482 does not apply to single-family homes and condos unless owned by a corporation, REIT, or an LLC with a corporate member; to owner-occupied duplexes; or to deed-restricted affordable housing. The Act is in effect until January 1, 2030. Not legal advice — see the California landlord–tenant guide.

Building characteristics
Units4
Floors2
Year built1917
Total area3,816 sq ft
Property typeMulti-Family Residential
Tax statusNone
Blocklot1523018
Ownership

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

Owner name
Mailing address
1870 8th Ave San Francisco CA 94122
Last sale

Landlord portfolio

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

Unlock complete report
Multiple entrances & addresses

Included addresses

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

495 21st Ave, San Francisco, CA 94121
497 21st Ave, San Francisco, CA 94121
499 21st Ave, San Francisco, CA 94121
493 21st Ave, San Francisco, CA 94121
Augrented Insights
Initial analysis

The two-story, four-unit multi-family residential building at 493-499 21st Avenue in the Central Richmond neighborhood, built in 1917 and owned by Mary Loo Lau, has undergone significant renovations and faced various maintenance issues over the years. Most notably, the property completed voluntary seismic strengthening work in 2020, including garage door widening, and a substantial bathroom and kitchen remodel in March 2023 costing $50,000. The building has had recurring plumbing and maintenance concerns, evidenced by a 2017 complaint about mildew, mold, and plumbing issues, and earlier maintenance violations in 2001 regarding shower drainage, window functionality, and heating problems. More recent improvements include a complete electrical rewire of one unit in March 2023 and various unit remodels between 2018-2023, including bathroom and kitchen updates, window replacements, and the installation of modern amenities such as new cabinets, appliances, and lighting fixtures.

The property has experienced several significant issues that required attention, including a 2017 incident involving lead paint concerns and operational complaints about plumbing systems, which were addressed through multiple permits and repairs. A facade demolition without permit complaint was filed in 2022, though its current status remains unresolved as of the latest planning records. While many health and safety issues have been addressed through various improvement projects, including the installation of motion-sensor lighting in common areas and comprehensive plumbing upgrades, the building's history includes notable periods of maintenance challenges, particularly in the early 2000s and 2017, suggesting a pattern of addressing both routine and urgent repairs as they arise. Recent permits indicate ongoing investment in building maintenance and modernization, focusing on both structural integrity (through seismic upgrades) and unit-specific improvements.

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

Free account unlocks the full analysis — plus 2× more records across all data categories and the complete landlord portfolio.
Risk rating

How 493-499 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

Lower risk — safer than most nearby

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

Typical — about average for the neighborhood

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

Higher risk — riskier than most nearby

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

Neighborhood percentile
34thpercentile

Out of 2250 buildings in this neighborhood, 1485 are predicted to be safer. The band is relative to this neighborhood, so a share of every neighborhood falls in each colour.

RiskiestSafest
Predicted 12-month outcome
80%
No DBI
violation
20%
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 risk forecast
Low failure risk 20%
Estimated probability of receiving a DBI Notice of Violation in the next 12 months. Model: full_hgb_balanced.
Apartment reviews

493-499 21St Ave apartment reviews

Real experiences from people who have lived here. Share yours to help other renters decide.

Share your experience — Help other renters by leaving an honest apartment review

Loading reviews…

On the map

Compare nearby alternatives

This building and nearby alternatives, color-coded by risk level. Click any marker to explore.

The story over time

493-499 21St Ave event timeline

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

2026
311 Request Jan 19
Garbage and debris
furniture

See all 12 events

Full history back to 2020 — violations, complaints, permits, buyouts, and fire incidents.

Unlock complete timeline
Every record we have

Full data for 493-499 21St Ave apartments

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

Side by side

How 493-499 21St Ave compares to the neighborhood

This building against comparable properties in Central Richmond. Toggle filters to narrow the peer group.

Loading comparables…
Still apartment hunting in SF?

Look up the next apartment before you sign

Search any SF address free — no account needed to see the risk rating.

Simple pricing

Get the complete picture

Every plan unlocks the complete report: all 13 SF datasets, full history, landlord portfolio, and PDF & Excel exports.

Pay once

Report Bundle

For the buildings you're deciding on right now

$10one time

3premium reports

$3.33 per report · charged once, never renews

Each credit unlocks one building's premium report for 30 days.

  • 3 premium reports — AI executive summary included
  • Live data across all 27 public record types
  • 200 records per dataset
  • PDF & Excel exports included
  • Compare up to 10 buildings side-by-side
  • Credits never expire until you use them
Pay once

Apartment Hunter

For a wide search across many buildings

$39one time

30premium reports

$1.30 per report · charged once, never renews

Each credit unlocks one building's premium report for 30 days.

  • 30 premium reports — AI executive summary included
  • Live data across all 27 public record types
  • 200 records per dataset
  • PDF & Excel exports included
  • Compare up to 10 buildings side-by-side
  • Credits never expire until you use them

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

Watch 493-499 21St Ave
Get alerted the moment a new violation or complaint is filed.