"Mom" advice here: Assuming the OP doesn't have any camping equipment to start with - take what money you can muster, and buy camping equipment: sleeping bags, cots, a good tent, cooking gear. This stuff will last you decades, and doesn't tend to give problems. You will be able to travel farther and longer (and do more fun things), because you just saved thousands of dollars. (There ARE tents that can utilize the back end of an SUV, too)
Anything with wheels needs important maintenance and tires and extra insurance and license plates. Add an engine and house to that mix, and now the expensive part ratchets upward. Your fuel costs just shot upward - and a breakdown on the road just becomes a nightmare.
Remarkably, your kids will have the same amazing memories of places visited and sights seen, no matter how they got there!