Caravan Seasonal Storage

We have been storing our caravan in derby where we live at a local dealers. We are considering moving it to a site that offers all year storage with the option to use it onsite at weekends as we feel we will use the van more this way especally is we finish late from work on a friday. We still will be taking the van away at bank holidays and in the summer. Does anyone know a site that does this in or near to derby.