NADA is the National Automobile Dealer's Association located in Kansas City. Their priority is scouring the large national auto auctions and dealerships for sales prices of automobiles and light trucks.
The NADA RV Guide is where they take the original cost of a RV--and they project a 1st year's depreciation. Then they lower their guide price a certain percentage per month.
Because there is no such thing as a RV auction, the NADA RV Guide is essentially a work of fiction. But it's all bank examinors, bankers and credit unions have to substantiate the advance on their RV loans. It may not be right, but it's all they've got. Don't put too much worth on it.