Used TT + Truck -- buying from private seller??

Just because you purchase from a dealer, doesn't mean there aren't problems.
Usually, all they verify, is that all the appliances, slides, etc, work when you leave the lot.

We would personally, rather buy from a private party, who usually has service records, and knows the history of it.

If you do your due diligence, and have someone you trust do an inspection, I wouldn't be worried about a private party sale, in fact, we would lean more in that direction.