Rustoleum makes many different type of automotive primers in a rattle can. For small spot repairs, I think you get by with the rattle can primers. What you will find out is that the rattle can primers tend to clog the sand paper unless you let it dry forever. Once you use the good stuff (beit acrylic laquer or 2k urethane primer) you will never use the rattle can stuff again (except for small stuff that you not in a hurry to sand).
