A toyhauler might be something worth looking into. They typically will come with at least generator prep, sometimes a generator, sometimes a fueling station, so you can draw from the generator tank to refill your lawn mower, or motorcycles, ect.
Usually they have plenty of ground clearance - even with a fifth wheel.
Usually there is a large area in the back with no cabinets, set up to sleep a bunch of people when the toys are gone. You can also consider perminate bunks back there. Talk to a cabinet maker. You can also bring along a favorite recliner too! LOL
Normally they have a 60+ gallon fresh water tank, some even have a pair of 100 gallon tanks, but only in the larger 35'+ lengths. This becomes very helpful to stay out more than a week and still get daily showers.
Room for solar panels, very helpful to avoid running a noisy generator to keep the battery full.
SunElec.comGood luck finding something.
Fred.