original price to what sells for used 10 years later?

If you want to get an idea of REAL selling prices, rather than NADA guesses or "asking" prices, go to eBay and find a coach similar to what you would consider. Then look at COMPLETED auctions. Those with the price in green will give the dollar figure that someone was actually willing to pay. You will find that most coaches do not sell at their asking prices and those that do sell are sold at well below the NADA guide values.