Primer

I have always used a sealer before topcoat. Other day I admit I shot the top coat over a few coats of wet sanded urethane primer, JUST to see ! I still have a half gal of topcoat if needed later. This was a color change form what I did 7-8 years ago. Was it smart? I will see! lol
If I had sealed that size car 1 coat of a reduced epoxy would have done it, and maybe a qt total reduced!! Just a few bucks!!! lol