I'm a sole trader, so it works a little differently for me.
When I had my Amorok, I claimed the VAT back off the purchase price, but then was liable for the VAT on the sale price, so only saved the VAT on the depreciation, which wasn't a whole lot.
With the Caravelle, it was used, and being a 'car' there was no VAT to reclaim. The screen price was the price. Not plus VAT.
As far as tax goes, I simply put 80% of the vehicles total purchase and running costs against business use on my tax return as expenses. I can claim the VAT back on parts and servicing, but I don't on fuel. I'm told that opens a whole new can of worms.