Introduction New York City homeowners and tenants often assume that kitchen or bath upgrades follow the same rules across all apartments. In reality, they don’t. A co-op in Park Slope or SoHo  might only approve renovations once a managing agent signs off on insurance and DOB filings, while a rent-stabilized unit in Harlem or Astoria  can’t even change fixtures without HPD review. By understanding which filings apply — Alt-1 vs Alt-2, licensed trade work, or simple cosmetic