For what you're proposing I don't see the rig you described being able to suit your needs.
You'll need a diesel if you're pulling a 4k + toad. Very few, if any, 4X4 pickups weigh in at less than 4k. Even a Jeep Wrangler is 4700. You'll need more CCC than a skoolie short bus will provide. Extra batteries will add to your weight and reduce the CCC even further. 6V batteries are about 70# each. Water, necessary if living off the grid is 8#/gallon.
Full timing is not simply selling your home, jumping in a motor home and heading out into the country. Some planning is necessary. Since it seems that's what you're doing here, I applaud you for that, but get some basics under your belt....Dennis
