Lack of regular use is no doubt detrimental and poses some risks, not that risks don't exist with any used coach. Tires need to roll to keep their UV inhibitor effective. 365 tires need to roll to stay together. Seals and rubber products don't like sitting either. Even seated metals don't like to sit. I'll suggest a sitting coach will show you it's problems associated with sitting in the first 10K miles with most showing sooner. I'm pretty sure my coach needed fuel injectors at 75K as a direct result of non use.

I know many harp on service records. I too see the value, but from a different perspective than most. When records are available, I look for those records that will tell annual mileage. Many coaches sadly don't get offered for sale until the coach has sat unused for a few years.

Don't let an otherwise great coach slip by. Factor and extra $10K to $20K in risk money and do a lot of local trips to shake out the gremlins. They don't even need to be trips. Go out for 100+ mike show rides. Your goal being to find and correct the problems before you're out on the road enjoying your coach.