I used primer and then engine enamel on a bmx last year. Painted it living in an apartment complex and you can paint the frame in sections until it's dry and then hit the other areas if you don't have a true paint bay area. I used the car parked in direct sun for a few hours and a few days at the peak hours of daylight & heat to cure the engine enamel. Came out rather nice. Bought whatever dupli-color had at the local Home Depot or Auto parts store had. Just spray evenly and let it dry for an hour or two between coats to be safe & sure.