Graham,I am no expert on these USA RV things but I do know that many need Transformers and some electrickery to make all the electrical gear work.
It s a long way to the south of France if you find you have a problem, I know people who have imported their own RV motorhomes and had electrics converted by qualified electricians only then to find they go off travelling and have problems on location.
Even if you make a call and get an idea from the RV pro's I mention above about what they would expect to do and supply, you should be able to know that your own expert is going the righjt route before you have a problem.
ps. many RV's have come through Liverpool docks, before shipping the wise people have extras such as microwaves and auto sat dish gear stowed under the beds. Many a unit has arrived minus nice extras that have gone on route!