I'll take a shot at 1 and 3.
1) depends on the condition of the car. If you are just going to paint it without any major preparation, you can expect to pay around $1.5-2K. MAACO will do a very nice POS job for a lot less than that, maybe $500. But their quality is crap, Crap, CRAP!
If you want to have the car painted the correct way, this would include body filling and levelling the whole thing, you could pay in excess of $6K, but probably more like up to $3K for a decent job.
3) Any body kit that comes ready to paint, actually means that they are ready to be fitted, sanded and prepped, before being ready to paint!
You can do the body kit in your own driveway no problem. You'll most likely need some jacks and stands in order to have the clearance under the car for crawling around down there and test fitting. You can test fit the kit yourself. It will take time, but when you find something that needs to be sanded down, just take your time. Depending on the type of parts you get, you'll need some painters tape to hold certain pieces in place while you check fitment and clrearanced, etc. Also, some nice thick blankets around the car will help prevent scratching the parts up while you wrestle them around your car.
Depending on the kit you get, ask the shop that will be doing the painting, how they prefer to have the body kit, either installed already, or in pieces. I would think a solid black color would not matter if it were on or off the car,the problem sometimes lies in the metallic finishes.
You'll also want to de-badge the car, take the rear brake lights out, 3rd brake light, reflectors, vinyl stripes if you have them, lisence plate fastener hardware, antenna mount, headlights and directional lights, your running horse up front, and fog lights if installed. Then clean the hell out of the car before you take it in to be painted.
