original price to what sells for used 10 years later?

One major problem I have found is that several repair shops, Freight-liner, La Mesa RV, etc. have stopped working on ten year
old coaches. I bought two year old DP for $120K, now worth $20K.(and that's trade in value)
And it's in very good condition. Motor homes don't hold their value
very well, and older ones are almost worthless compared to original cost. I don't feel they are good investments except for the pleasure they give you.