I bought a maypole one from EBay and pleased with it. It's fleecy on the inside and made of breathable fabric. We bought it to protect the caravan whilst doing damp repairs. Will keep it on permanently to make sure we don't get any further water ingress. it's on the drive, so I check every couple of weeks to make sure there isn't any condensation.
Amazing family weekend with old steam engines, classic car displays, market stalls, and full catering and bar. And camping on site - Save £25 by booking in advance.