439 Harkness Ave, San Francisco, CA 94134

The two-unit residential building at 439 Harkness Avenue in Visitacion Valley, owned by Jason Tan and Mandy Li, has an extensive history of unauthorized construction and recent maintenance issues. Built in 1909 as a two-story flats/duplex structure, the property was the subject of multiple complaints between 2000-2008 regarding illegal construction, particularly concerning unauthorized units and unpermitted deck and room additions in the backyard area.

These violations, which were investigated by both Housing Inspection Services and the Building Inspection Division, were ultimately resolved but indicate a pattern of non-compliance with building regulations during that period. More recently, from December 2024 through January 2025, there have been numerous municipal service calls related to the property, with several reports of garbage and debris issues, including liquid spills and abandoned items such as mattresses and garbage containers.

Notably, there was also a sewage backup incident in January 2025, though this was promptly addressed and resolved according to utility services. The property is currently facing two persistent infrastructure issues: a lifted sidewalk that represents a potential hazard, and a recent report of a manhole cover being displaced, though this latter issue has been resolved. The building's maintenance history, particularly the recent spike in service calls related to garbage management and infrastructure concerns, suggests ongoing challenges with property upkeep, while the historical pattern of unauthorized modifications indicates past difficulties with proper permitting processes.