Speaking as a former owner of a body shop with some familiarity with restoration work, be very suspicious of any vehicle that's been prime-coated. The flat, non-reflective surface finish can hide a multitude of problems with the sheet metal. At the very least, you'll have a big job ahead of you sanding the extra layers of paint off to get down to a surface that will accept a good paint job. That primer was probably applied over years of accumulation of dirt, wax, and road film, so if you apply a good paint job over it, it will peel in no time.
I'd suggest an up-close inspecton, either in person, or an unbiased opinion by someone without a financial interest in the vehicle. Cross-country deals bear too much resemblance to buying a pig in a poke to me!
Jerry
