How do I show the purchase of a van and claim the vat back?

Hello Shaun20, 

Welcome to the Community page, 

If you purchase a vat, you can simply enter an expense entry with a vat on it, like 20%, automatically, the vat of that will go against the reclaim on the VAT return. 

or 

If you wish to enter a VAT only transaction, you can open up an expense 

1st line £1.00 VAT 20% (any expense category)

2nd line -£1.00 NO VAT (same expense category as the first line)

Then you have to change the VAT amount on the bottom left