Hi Tricky,
I've been to the UK (I'm going to use the UK as a starting point for argument's sake)
but had never thought to do it by RV. However, I have googled a bit and found some links to
some websites which might be helpful.
http://europeforvisitors.com/europe/pla ... rhomes.htm <<<<< general info and some links
http://www.ukmotorhomes.net/ <<<<<<<<< RV's for sale, rent, and insurance costs.
http://www.motorhome-international.com/ ... &maincat=1 <<<< more Western Europe RV info.
http://www.transitionsabroad.com/public ... rope.shtml <<<<< a personal RV in Europe story.
I know very little about RVing in Europe, but, why not??? I'd imagine there are probably scads of Sprinter van based conversions over there, if that would do, although I'm not sure if they would sleep six. Maybe some of the Sprinter based RVers on this site could enlighten as to what the max sleeping space might be, considering room for 2 adults, and the rest children?
You might also try PMing or asking a member called "daytripper". He's from the UK I believe. Might be able to help?
Good luck,
Mike.