Always extra cautious when towing , my rule is check & check again seen some horrendous accidents involving trailers/caravans , problem is some folk have no idea how to load them & even less how to manoeuvre & drive when towing.
the same folk also don't know/care that trailers need occasional maintenance. They're the ones you see with wrecked tyres that have shredded the caravan side, have shed a wheel and flipped while still attached to the car or that have become unhitched. It's even easier to overload a small cheap trailer than a van, and the consequences are worse.
Having to take a test to tow was necessary, but the weight limit was a bad idea: it should have been to tow any trailer.
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I have a friend who teaches towing technique for the C&C club some of things he has seen are horrendous caravans with 16 year old tyres on inspection was one & some of the loading of them is beyond stupid. Can't remember the last time I saw any spot checks on caravans by the Police nothing seems to be done now till after an accident.