I do a lot on my cars, but I no longer do paint. Just not enough patience left to deal with it. I used to spend HOURS doing the body work til I felt it was perfect, then get the car to the painter who invariably pointed at a few areas and said "Gee, that's pretty rough - I'll have to spend some time making it right."
El-Cheapo paint will cost you twice - it'll be cheap when you get it done, but it'll look OK at best and you'll probably get it done again in a few years. Plan on around $1 grand for that.
Quality prep and paint will cost you, but the finish will be much better and people (mostly everyone) will notice. Plan on $2K - $6K for that, depending on where you go and what gets done, with a sweet spot of $2,500 or so. I spent over twice that on my car and the finish came out great and has lasted since 1999.