Fine. Here's my free advice. Keep in mind not all of these ideas are implemented at my own shop, but most are and others are 'in the works'.
Bay size: 15'x32', 10' overhead
door.
flooring; concrete with 'runners' on either side of the vehicle spot, either industrial carpeting, non-roll-up rubber mats or snap together plasitc tiles.
equipment; extractor, wet vac on a rubbermaid janitors cart, air compressor, tank sprayers (for g.p., dressing and window cleaner), gravity fed paint gun for express polish application.
more on the bay; should have plenty of NATURAL light, plus hi-output fluorescents. white painted walls down to 3" above the floor. paint with washable paint (very crucial if it's to be kept clean).
layout: vac carts are movable and can store your sprayers, chems, detail tools and trash containers. That's what I love about these carts. Compressor wherever it's out of the way. Same with extractor, though if it's a tiny one it could also be stored on the cart as well as a fan and ozone generator.
What's done in this bay; all aftercare: express wax, shampoo, window cleaning, dressing of all types.
what else did you ask about?