"CVD".....I don't think your equation will work for a few reasons. Too many variables in RV's from a loaded coach to a stripped down model. In my situation, the sales of my coach, brand and model, boomed after I bought it. I've had very little loss in depreciation. On the flip side, base model coaches and those perceived to be problematic can drop like a rock compared to others.
I've ALWAYS found the best way to determine price is to find similar coaches and average them out. You can usually get pretty close to what they're worth by looking at many coahces, including similar designs and years, even in different brands. As an example, 2005 Class A gassers in the 32' range will be pretty similar, since they all have the same chassis.
