I've noticed this coach on consignment and even though it's over the price point your friend is wanting to spend, he may be able to negotiate at least a slightly better price.
The reason I feel it just may fit what he's looking for is that this American Heritage coach is built on a Spartan Liberty chassis. This is a heavier-duty chassis. It also has a 15,000 pound towing capacity which is, again, more than the average diesel pusher with tag ...the "run of the mill" DP with tag will usually have a 10,000 lb towing capacity. The ad describes it having a 600 HP Cummins but I'm not sure if that's accurate or not. It's 600 HP but I'm kind of thinking it could be a CAT C15. I'm not sure but maybe somebody who owns one or in the know can confirm. Hopefully it is a Cummins, however. It's also equipped with an Allison 4000 6-Speed.
Nevertheless, A heavier-duty coach with a 600 HP engine and 15,000 pound towing capacity might be something that could be attractive to him. If his stacker is going to exceed that weight, he should be looking for an older Prevost, Newell, Marathon, etc. that can tow up to 20,000 lbs.
Not sure if this coach is still available but might at least be worth checking out.
2006 American Coach American Heritage -- consigned (MHSRV website)