have you never heard of a PPI?
if you're dropping 20K it behooves you greatly to have "professionals" check it out. yeah, if you're buying some project or like a 6K roller or whatever, sure take your car buddy that always keeps a gun in his boot with you for another set of eyes and to BS with the owner while you writhe around under the car with a flash light.
but any more than that? i'm coming with a fine toothed comb.