DRV's aren't terribly rare but I still feel the nature of the beast justifies a nationwide search ...
There are a couple of dealerships that specialize in DRV. I was in touch with Whiskey Mountain in Mesa AZ. Very good about giving advice. Their rigs are a bit above market but typically have new furniture and sometimes new flooring. Rolling Retreats in Elk City OK is another, haven't talked to em but they get good reviews. They can do your roof for ya if it needs it. I would cheerfully get a rig shipped out from either place, if they had the exact one I wanted. I'd still get it inspected of course but they have inventory and know what they are talking about.
DRV had some innovative layouts. I'll draw your attention to the Houston. The bedroom/bath layout is SUPER nice for full timing. Also note the long, opposed slides in the living area, really opens up that space. They kinda "mix and match" those features across several of their models, worth keeping an eye out for
Some of those layouts come with an extra toilet. Which is nice I guess when you're on the road (easy to get to at a rest stop), but for living aboard I'd rather have the extra storage space
I also like their rear kitchen layouts. Maybe not the best for towing but seem very liveable. Whiskey Mountain had a gorgeous example in your price range, unfortunately it looks like they sold it
Well built rigs, kinda heavy but that's fine if you're staying in one spot, just gotta get it delivered. About the best frame on the market for a 40'+ rig, but you still gotta check it. You can see the stress points if you crawl around in the forward compartments and look behind panels in the storage compartment. Look for cracks (and if it's a Florida rig, look for corrosion due to flood damage). The Moryde independent suspension is glorious but needs maintenance, which doesn't come cheap. Your average RV inspector may not be familiar with either one, so search the forums and also check out the Moryde website for inspection tips.
Most (not all) have rubber membrane roof which may be reaching the end of its lifespan. I would personally consider a fiberglass roof a plus and in any event I'd look very closely at that.
Beyond that, it's the typical stuff you might find on a 10+ year old RV. Check your floors, specially the bathroom and slide floors. Arizona and Florida are great places to shop for a rig, but sun damage ain't gonna get better over time and may limit where you can stay. Be advised, you may be replacing furniture, electronics, flooring, AC, fridge (DRV was an early adapter of residential refrigerators, and believe me you want that, long as it isn't Samsung). But, they have nice bones. The older ones have gorgeous woodwork (even the newer ones aren't bad). Good insulation, which makes a huge difference comfort wise. Still, 3 AC's is a plus ... they also had a cold weather package (two furnaces, tank heaters) which can come in handy. Not as a big a deal in New Bern, normally, except for this year eh.
Just get it inspected, AND look it over yourself. Nice rig, we are full timing in our Santa Fe and we love the durn thing
