Dave,
Take a look at this web-site www.eriba-amiga.co.uk/pre_holland.html and look at the two or three stories about buying in the Netherlands.
A lot of Eriba owners source their vans from Holland because: they're in much larger supply both new and pre-owned, the prices are lower, and you probably will have a larger choice of factory fitted options.
What to look out for:
1. Obviously the mains power points will be the Dutch / German Schuko type - Actually we have always had these fitted to our Eriba vans because they have better insulation / protection than the UK 13 amp plug and socket. If you don't know the Schuko socket and plug, it's sort of a half way house between the UK 13 amp thing and the blue IP44 splashproof connector you use on-site.
And all of our electrical stuff is fitted with Schuko plugs (CEE 7/7 type) because we buy a lot of electrical stuff in France or Holland, or self fit a plug in the UK.
But if you want UK sockets, then factor in about