All of my advice is based on general car hauling info that I know, rather than from RV-specific experience.
A small flatbed trailer is always easiest on the vehicle being towed. If you tow a vehicle flat on the ground then you should probably drop the driveshafts from the transfer case and transmission tailshaft to minimize the amount of wear on the transmission and transfer case while the transmission pumps are not operating. You'll probably need to cover the the slip yoke on the transmission to keep fluid in and dust/dirt/rocks out. You'll also have to maintain the vehicle's suspension, wheels, wheel bearings, and to a lesser extent, brakes (disc brakes don't fully back off) as if the vehicle is being driven.
A front wheel drive vehicle can be towed fairly easily on a dolly, but like the flat tow, attention needs to be paid to the rear suspension, wheels, brakes, wheel bearings, and the like just like the vehicle would get if driven.
If I were doing this, I'd plan on towing a Jeep Wrangler, or maybe a Jeep Patriot. The Wrangler has great off-road capabilities, is reasonably easy to maintain, and is available in different wheelbases. I'd probably try to stick to previous generations rather than the current model as previous ones are a little smaller and lighter, and if I could find a previous generation two door Wrangler Unlimited then I'd opt for that, as it's large enough for carrying five, is large enough for carrying parts, supplies, tires/wheels, and the like. The Patriot isn't quite as versatile as the Wrangler, but is still pretty good, and is also capable of fetching things, and is lighter than the Wrangler if memory serves, and is shorter in height.
From what I've learned in shopping for a car hauler, aluminum car trailers can weigh in as little as 900 lbs, versus 1500lbs for a steel trailer. I'd even consider, if I was you, in seeing what could be custom built for the towed vehicle in question, based on its weight, needed support (like tools and extra wheels and tires), and the like. A general purpose car trailer might weigh a lot more than a trailer designed specifically for a Wrangler or Patriot, or some other small 4x4...