Ken brings up some valid points regarding towing a caravan or trailer. I dont think they ever have any form of MOT to inspect there road worthyness.
On the subject of towing, 40 odd years ago many of us could make and fit our own towbars to our capri's and cortina's .....we cannot now . They have to conform to a BS standard. Same with trailer's , I've made a few years ago but now they should have a name plate with kerbside weight stamped on it and really should be inspected and passed by VOSA. The loophole here is ,you are allowed to repair an old trailer without it needing inspected. Mine is newly made but with an 30 year axle. Dont know how my insurance company would see things if I had an accident. So, some very interesting points to ponder over.