Sorry guys about the exterior coach width typos in my two earlier posts ... guess I hadn't had enough coffee before I posted! My corrections in the two earlier posts now show in red.
Our widebody width in a 24 foot Class C has been my only concern to date in taking it off-pavement. However, as of yet it has never been an issue - just a "worry" for me.
For what it's worth, I spend some time over in the Boondocking and TC forums. In viewing the many posted photos over there showing various TC rigs in camping spots, I see very few places where it looks like my Class C couldn't have gotten to. Of course the photos usually don't show what difficulty they may have had GETTING INTO some of those places!
P.S. I consider rigs like Ron Dittmer's an excellent starting point for an affordable off-pavement Class C if it had a limited slip differential, was on the E450 chassis, and was 4X4 ... if it also meets the other criteria on my earlier list.