Which is cheaper - new or 3-year old over 8 years?

A 3 year old MH is about equal with a new one as far as usage, unless it has been abused. I would rather have a 3 year old MH and $100,000.00 in my pocket than a new one with zero dollars.

MH for MH they sit on the same chassis and have the same appliances. The only difference is one has been used for 3 years part time. Routine maintenance is the same on a used and new.

Your list of Newmar, Tiffin, etc. MH are good reliable manufacturers, even Prevost and Newells have problems like all the rest....