The first conversation should be about your hours, not about color. A restaurant that closes at 10 can be painted overnight. An office can be done over a weekend or one section at a time after five. A good painting crew builds the schedule around when the building is empty.
Before we arrive, clear what you can from the walls and move anything fragile. We'll cover and mask the rest, but the less that's in the room, the faster the work goes and the less risk to your equipment.
Low-odor paints make a real difference in a space that reopens the next morning. Ask for them. Scrubbable finishes in satin or semi-gloss are worth it on high-traffic walls, hallways, and anywhere near tables and chairs.
Finally, get the scope in writing: which walls, which products, how many coats, and the schedule. That way you know exactly what's happening each night, and the final invoice matches the estimate you approved.