[HardcoreZ28]

To do a paintjob right will cost you atleast $1,000 in good materials. And that's with minimal bodywork. The labor is where it gets expensive. For $5,000 you can probably get an excellent driver quality paintjob but if you're looking for a show quality job on something that needs little to no bodywork you'd be in the $8-9,000 range and anything requiring more bodywork would easily put you above $10,000.
You're on the right track though by offering to prep the body yourself, just be sure you do more good than harm.
If you'd like me to look at the car and give you a quote feel free to contact me.