A co-op means you own shares in a corporation that owns the building, not the unit itself. Boards tend to review more closely and have more discretion to say no, because the whole building's structure and systems are shared corporate property. A condo means you own the unit outright; the board's authority is usually narrower and defined by the alteration agreement, though structural and shared-system work still needs approval.

• Anything touching shared systems - plumbing risers, electrical risers, structural walls, HVAC that serves more than one unit.
• Exterior or common-area visible changes - windows, balconies, anything seen from a hallway or the street.
• Noise and construction-hours rules, which are often stricter than city code and vary building to building.
• Insurance and liability requirements for the contractor, separate from what the city or county requires.

A common assumption is that you get the permit first, then go to the board - or the reverse. In practice both processes usually move at the same time, and each one can surface a requirement the other didn't. Drawings clear enough for both audiences from the start save real time later.

Boards are not architects, and most board members are volunteers reviewing a project on top of their own jobs. Clear drawings, a plain description of what's changing and what isn't, and a named point of contact for questions go a long way toward a fast approval instead of a slow, back-and-forth one.

The Long View - a full gut renovation in a SW Waterfront co-op, working around drain lines and an electrical panel that couldn't move. The board approved it alongside the city process, with drawings built to answer both audiences from the start.