Most price by scope (rooms/square footage + prep) rather than pure hourly. Prep quality (patching, sanding, masking) drives both labor and the final finish.
Surface cleaning, patching, sanding, caulking where needed, protecting floors/furniture, and priming stains or repairs before paint.
Commonly 2 coats for walls, plus primer if needed. Deep color changes, glossy-to-matte transitions, or stained surfaces can require extra steps.