You are both in a hard spot - You have found some things wrong and the owner still wants his price and has taken offense to the inspection report (not too different than buying a house). He isn't obligated to lower the price for the inspection items, so if you really like the coach and you think you may lose it to another buyer, maybe $6K isn't worth haggling about. The next coach may be way worse.
In reality I kind of look at tires, batteries, shocks, engine maintenance, as all kind of hidden expectations you have to budget for buying a used RV, and if they don't need them it's a bonus! The worse that could happen is the seller offers to fix it up for you - his way - and you get the cheapest of everything.
