First off, talk about changing the color of your car at your own risk around here. I was almost virtually castrated for it.
Secondly, paint jobs are very expensive, especially done well. i.e: painting door jambs, underhood, trunk......
There is almost no way to guesstimate what it would cost for you, but I will try. 6-12k depending on how straight you want it and how clean it is to start.