As mentioned above, the variables are immense. It also varies from region to region.
I restore muscle cars in northwest Arkansas and if the customer brings us the car with the engine removed and all of the interior and glass removed, we disassemble, soda and media blast, epoxy prime, urethane or polyester prime, block, seal, paint , buff and reassemble. This includes preassembly prior to paint to check body lines and panel alignment. The prices vary but usually start at $6000 plus materials. Rust repair and body repairs are extra. Painted interior parts are extra. Painted suspension parts are extra. We're finishing a rust free '67 matching numbers hemi 4 speed GTX right now. The total bill will be around $8000+. That's probably a lot cheaper than most parts of the country. We're usually backlogged three years or more. There's no such thing as a quickie paint job. It always (repeat...always) snowballs. There's no place to stop if you want the car to be nice. I've seen guys take off one part and end up restoring the entire car. Once the paint is finished, the fun begins. If the budget's tight and you want an average paint job, you might find a technical college that might take on the job. Base/clear materials inc primers, etc. usually run around $1000 for the good stuff. Higher for red. I bought a gallon of red mixing color Friday and my cost was around $500. Before you let a shop paint your ride, check with past customers (as many as possible). Quality work is important, but find out how long it took to complete and how the shop wanted to be paid. A reputable shop usually wants around $1000 to start and will designate a set amount at each stage of the job. We usually ask for $1000 down, $1000 after media blast or soda blast, $1000 when the car is ready to paint and the balance when the car is finished. Some shops work strictly by the hour and charge you for the work performed that month and if the bill isn't paid , the work stops. I've seen shops around here quote a stupidly low price, demand the full amount up front and never finish the car. The owner ends up picking up the car in a thousand pieces (some missing or sold by the body shop) and get totally disiillusioned.
Remember, you get what you pay for. Cheap paint jobs look cheap.
Good luck and I hope you find a good shop.