During the many years that I've owned/enjoyed Class A motorhomes (five pre-owned gassers and (finally) a special-ordered, brand-spanking new large diesel pusher). The best AND worst experience was my diesel pusher(very long story). Today, NOW that there are many very good deals in the type of diesel pusher that I like, I would NOT hesitate to buy a clean one-owner DP. This comes AFTER I gained quite a bit of experience in what to look for.
In my defense: with regard to my DP, we ordered new because in early 2003 there NO used units that had all the "deal breaker" features that we wanted. We also wanted to sample brand new. Where I failed is in finding out ALL the details of the design/construction of the "all fiberglass" roof that NEWMAR put on our Dutch Star (in 2003). In my opinion, I got "water for chocolate". And, it was NOT all my fault. But, to argue my case would've cost more than to learn and execute the fix on my roof.
BTW I now have a lot of roof-repair experience that I hope I will never have to use......:B