Free SF apartment background check

3339-3345 20Th St

Inner Mission, SF 94110 3611059 4 units · 2 fl · 1885

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 Inner Mission
Above average
avg 2.6
6
FewerMore

This building has 6 novs (7y), above the Inner Mission average of 2.6.

Rent & eviction protection

Is 3339-3345 20Th St 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 1885
2 or more units
4 units
Property type
Multi-Family Residential
Zoning
NC2
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
Units4
Floors2
Year built1885
Total area4,426 sq ft
Property typeMulti-Family Residential
Tax statusHome Owners
Blocklot3611059
Ownership

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

Owner name
David Glen Congreve Quinby
Mailing address
Quinby David Glen Congreve 3341 20Th St San Francisco CA 94110
Last sale
080415

Landlord portfolio

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

Unlock complete report
Multiple entrances & addresses

Included addresses

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

3341 20th St, San Francisco, CA 94110
3339 20th St, San Francisco, CA 94110
3345 20th St, San Francisco, CA 94110
3343 20th St, San Francisco, CA 94110
Augrented Insights
Initial analysis

The 4-unit, 2-story multi-family residential building at 3339-3345 20th Street, owned by David Glen Congreve Quinby, has a complex history dating back to its 1885 construction. The most recent significant issue involves an active complaint from May 2024 regarding unauthorized electrical work and contractor payment disputes in unit 3345. A substantial repair project is currently underway as of June 2024, addressing failing and cracked plaster in one unit with a budget of $30,000. The building underwent several important safety upgrades in the past decade, including the installation of a fire sprinkler system in the garage area in 2011-2012, garage renovation work in 2011, and electrical system upgrades including new service with 5 meters and panels. Multiple building violations were recorded in 2002, including issues with damaged walls, mold, and various safety concerns, though these were all abated by June 2002.

The property has experienced several concerning incidents over the years, including multiple complaints in 2010-2011 regarding unauthorized construction, including questions about a garage being built without proper permits. A significant complaint was filed in December 2018 regarding potential unauthorized unit conversion and non-residential office use by the owner. During 2024, there have been multiple 311 calls regarding street cleaning issues near the property, including reports of human waste and debris. Recent parking enforcement activities were documented in October 2024, with citations issued for driveway blocking. The building has undergone various improvements over the years, including kitchen and bathroom remodels, furnace replacements in 2008, and significant electrical upgrades in 2011, though some work has been performed under questionable circumstances, as evidenced by multiple complaints about work beyond permit scope and permit-related issues.

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 3339-3345 20Th St'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
62th percentile

Out of 2380 buildings in this neighborhood, 904 are predicted to be safer.

RiskiestSafest
Predicted 12-month outcome
70%
No DBI
violation
30%
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.

NOV rate, owner's portfolio

Per-building NOV rate across everything this owner manages — high rates signal pattern neglect.

12-Month severity forecast
No violation 67.6%
Moderate concern 24.8%
Severe concern 7.6%
Estimated probability of receiving a DBI Notice of Violation in the next 12 months at each severity level. Model: full_hgb_balanced.
Apartment reviews

3339-3345 20Th St 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.

Buildings nearby
Loading…
The story over time

3339-3345 20Th St event timeline

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

2026
311 Request Apr 08
Blocking driveway cite tow
Parking Enforcement
311 RequestJan 13
Sewage back-up discharge

See all 10 events

Full history back to 2024 — violations, complaints, permits, buyouts, and fire incidents.

Unlock complete timeline
Every record we have

Full data for 3339-3345 20Th St apartments

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

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.

Report Bundle

For the buildings you're deciding on right now

$10 one-time

~$3.33 per building. No subscription ever. Each credit unlocks one building's premium report for 30 days.

  • 3 full AI-powered reports
  • Download PDF reports
  • Advanced safety analysis
  • Compare multiple buildings
  • Credits never expire until you use them
  • Full public records (200 rows per dataset)
Buy 3 Reports — $10

Apartment Hunter

For a wide search across many buildings

$39 one-time

30 reports — ~$1.30 each. No subscription ever.

  • 30 full AI-powered reports
  • Download PDF reports
  • Advanced safety analysis
  • Compare multiple buildings
  • Credits never expire until you use them
  • Full public records (200 rows per dataset)
Buy 30 Reports — $39

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

Watch 3339-3345 20Th St
Get alerted the moment a new violation or complaint is filed.