Upper West Side.

Three factors: (1) co-ops are owner-occupied with professional building management and capital reserves that drive fast violation resolution; (2) the housing stock — large pre-war elevator buildings — has fewer per-unit complaint origins than walk-ups; (3) UWS tenants generally file fewer 311 complaints than tenants in stress-tested rent-stabilized stock. The result is genuinely low open-violation counts.

The UWS walk-up stock west of Amsterdam and the smaller side-street buildings in 10025 average higher open-violation counts than the marquee Central Park West co-ops — but still below most Brooklyn or Bronx walk-up neighborhoods. The classic heat / plumbing / lead pattern applies. The audit's class breakdown matters more than the headline count.

Yes in the older walk-up and small elevator stock, much less so in the larger Central Park West and West End Avenue buildings, many of which converted to co-op in the 1980s and 1990s. The audit pulls DHCR registration data so the building's current stabilization mix is transparent before you sign a lease.

10023 covers the southern UWS (West 60s to mid-70s, around Lincoln Center) with a mix of pre-war co-ops and newer post-war high-rises. 10024 covers the central UWS (West 70s to mid-80s) — the densest pre-war co-op cluster and the highest median prices. 10025 covers the upper UWS (West 90s to 110th) with more walk-up stock and slightly higher violation counts on average.

Yes — large parts of the UWS sit inside Landmarks Preservation Commission historic districts, and unpermitted façade or window work creates LPC violations in addition to DOB filings. The audit pulls DOB permit history and flags open work without a closed sign-off; for landmark-district buildings, LPC issues are a separate layer worth asking the seller about.