Hi Richard
We used to keep our caravan in France courtesy of Camping Le Vivier aux Carpes at Seraucourt le Grand (see www.camping-picardie.com). The van stayed on the owner's farm throughout the year and was brought to the site for us when we wanted to stay. Seraucourt is about 10km from St Quentin. We were able to arrange insurance through them as well - the only problem at the time was arranging payment, but I'd imagine that this is now a lot easier. It's a while since we were there but it may be worth a try. The site manager, Christiane, speaks good English - the site is C&CC Carefree recommended and is beautiful.