About NADA RV Prices:
I have heard that the reason that NADA prices are so skewed, both high and low, is twofold.
Because so few RV's over 5 years old are taken in as trades, (dealers don't want to have to deal with higher warrantee costs associated with older rigs) most are
sold in private party transactions.
In many (most?) cases this results in the buyer reporting a somewhat "adjusted" purchase price to reduce the sales tax due when registering. Last year, when I
sold my 1989 Toyota Sunrader pop-up motor home for a bit under $12000, the buyer reported a purchase price of $3000 (and saved about $750 in sales tax.) This lower number goes into the public record and is what NADA uses, in part, to determine value.
In the case of newer trailers, dealers do resell them and point to the MSRP of new trailers (a price at which they are almost never sold) when the buyer asks about price. Hence, dealer resale prices are much higher than private sales and are reported at 100% of sales price, pushing those prices up, at least for the first few years.
How much of the forgoing is accurate? Who knows, but it does seem to reflect what is happening in the marketplace.