Private seller or dealer

Hi all, my first caravan, an eldis mistral gtx is about to go to the caravan graveyard in the sky!!!  We bought it on a whim 5 years ago when is saw it adverised on a for sale notice board at work ( up to this point we hadnt even considered a caravan!)

We have a holiday booked in 2 weeks so need a new van pretty quickly so Im looking for a little advice.

We have approx £3 K to spend and are now wondering whether it is better to go to a dealer or to a private seller. I have looked around and its obvious that you can get more for your money privately but Im concerned about ending up with something that looks great on the surface but is rotten underneath.

Any advice would be greatly appreciated; what do we need to look for, what year can I expect to get for £3k. ( we ideally want a 4 berth for the size but a 2 berth is fine)