Good luck, piney423! In addition to the great information posted above, I think it also depends on how well the previous owner took care of the PUP. We were fortunate enough to buy ours a few years ago from a co-worker's parents. They were the original owners (bought it new in 1994) and took excellent care of it. They hadn't used it in YEARS when we bought it; but opening it up you would think that they religiously cleaned and cared for it. It does have the canvas smell from being outdoors, but that seems to be pretty unavoidable, and airing it out helps quite a bit.
Happy camping!!