Eurotech Motor Mover in good working order. Not been used for 18mths.
It was used to move a boat on a trailer, think it was about 2 tons.
It has a solid tyre and is fitted to the caravan /trailer by fitting it to the jockey wheel. (You remove the jockey wheel). It does need a 12v battery to work it. I have one to demonstrate it working but it's very small, and I don't think it would powerful enough to move caravan.