As a car guy, I carried a NADA guide in my pocket most days of my 24 years in the industry.
They don't call it the NATIONAL AUTOMOBILE DEALER'S ASSOCIATION for nothing. They have nationwide auto auctions that they can get sales information from to come up with more accurate pricing.
But when it comes to recreational values, there are no national sources of prices for used units sold. And the chances are the person crunching values doesn't know the difference between a Class B and a Class A RV.
They take a projected selling price, and then depreciate the unit by a set percentage every month. In other words, the prices quoted are works of fiction.
But it's the only nationwide source of information on RV's--right or wrong. And it's the bible that bank examiners and government bank regulators have to substantiate the amount advanced on bank/credit union loans.
As long as the values are not based in reality, we've got to play games with the banks and credit unions.