"No VAT" vans

[MartinM]

Hi all

I'm looking for a small van, probably a Caddy but open to suggestions and sometimes see "no VAT" on ads for used vans. II'm self-employed but not VAT registered. I know VAT is added to the windscreen price on all new vans but can someone explain the criteria here?.Am I right in thinking that main dealers have to charge VAT on used vans?
Ideally I'm looking for something with low mileage that I can pay with finance.

Thanks in advance