itsyRV:
yes, what you say is generally the reality we face (if we are unfortunate to be on the receiving end) when dealing with the whole DV business.....to be honest, just reading all the folks on this forum, it is an eye opener. The one thing we have learned is that DV is REAL when it comes to significant value reduction on motor homes. Some consumer reports show up to 50% reduction in trade value, and that was with minor damage, BUT the coach had an accident (carfax) report attached to it. Also, its a legal obligation that if you sell private, you must inform all and any potential buyers, of all accidents reported!
That is a major problem with RV's, you don;t have tons of data to obtain values the insurance company will accept (or accept without fighting you tooth and nail). You are also faced with recorded "sales" that often can jump tens of thousands just by geography, time of year, or even from used RV dealers right next to each other.
This is why many say to use your own insurance as you have a contract with them and that contract spells out exactly what they must do for you. If it sets a standard for diminished value, they must abide by it. When dealing with the other party, they only have to do what the state regulators say them must do; often it's pretty weak protections at best. The other insurance company's duty is to save themselves money and protect their client. You are not their client so you have far less rights. Your insurance company has a duty to you, their client, to make it right so you have a while lot more rights and protections with your own company.
From past experience, you'll need to get enough comps from wherever to either satisfy them or to satisfy a state regulator that you have done about all that is reasonably possible and hope they can intervene without you having to sue.