epoxy primer can be brushed and rolled
as you progress, and epoxy gives you a much longer window before you carry on with the final work, or hire that done, it just needs to be scuff sanded if it's left longer than a week or so - you will be happy you used epoxy primer later ..... of course this is assuming you're going to do a proper job of prepping the body, including stripping as much as possible to bare metal, which process will give you lots of time to consider the finish coat

Bill