I once had a little, i.e, 8ftX9ft Caravan, and when the undercarrige started to go, and became a little less road worthy, i bought a Toyota pick up, and had an enginering firm strip the back of the pick up, and mount the caravan to the Chassis of the pick up. a few cosmetic panels and a spray job, cost me what would today be under €1000 (this was 1987) and i got many years enjoyment and sold it on eventually to a retired couple, who enjoyed further happiness. small, cheap nothing wrong with it at all. Sadly no pic though
For something slightly more practical, you could try something like this!

Pic Courtesy of the Motor Caravan Club of Ireland.