Be a little wary of a vehicle that's in primer. The dull surface can hide a lot of little dings that would show up if it had some gloss to the paint. Also, if it's been exposed to any weather, that coat of primer will have to be sanded away entirely,as it's porous, and any attempt to paint over weathered primer will probably result in peeling paint pretty quickly. It soaks up moisture like a sponge, and a top coat traps the moisture between the paint and the metal. Bad news!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!