Folks talk loosely about RVs as houses on wheels, and that sounds reasonable enough. There's nothing new about hitching wagons to livestock; caravans have a long history. But modern travel trailers (dealers like to call them coaches) are less like moving houses and more like flying freighters. There is the towing. The truck needs horsepower, an integrated braking system, a hitch receiver the size of a washing machine, a rear camera, special side mirrors. There are torque wrenches, cotter pins, ball mounts and, in my case, a large wooden mallet I bought just so I could hit something that didn't work.