I wouldn't consider a Sata RP a "spray can". Nice gun though, same one I use. You could save several steps by using PPG DPLF Epoxy Primer over the sanded plastic. It comes in 3-4 colors & acts as a primer, sealer & adhesion promoter. I would wet sand with 600 before final painting if you don't want to see sanding scratches, ect. If you are painting in your garage use a single stage color to avoid catching dust/dirt in the clearcoat. Keep in mind that any of the modern catylized paints can kill you & you should be wearing a breathing system/tyvex suit/ect.
90 535im
02 R1100S, 87 R100S
76 R90/S,73 R75/5
Alfa Romeos- 65 Giulia Spider Veloce
& 66 Duetto 1600 Spider