Tracy, i recently looked into the idea of bringing a new van from Holland into the UK. I would imagine your situation is similar and as such the vat/paperwork scenario likewise.
I have two options:-
1 - Buy van in Holland with NL vat paid, get given relevant paperwork by dealer, pay UK vat on entry to UK or in advance. Claim NL vat back
2 - From a very limited number of dealers set up for export in Holland, buy van with NO vat paid, get given relevant paperwork by dealer, pay UK vat on entry to UK or in advance.
I would advise contacting the tax office, which will probably be a protracted e-mail chain, and seeing if you can get a UK dealer who is set up for this type of "export". I'm guessing ALV and Red Lion would be the closest to the ports for you to cross over and collect.

Best of luck - Colin

The tax office told me that when bringing a van into the UK from Europe no import duties need to be paid, just the vat. I would imagine the situation in reverse is the same.
It crossed my mind that you could just drive through, and I have to admit that if the van was not bright, shiny and new this would be a serious consideration.

Colin