I would get a written quotation for the finance, check that the figures stack up to the on screen quotation for the car i.e. finance quotation total amount payable is new car on screen price plus interest charges. You may also want to check the interest rate is the same as the offer rate quoted on the VW website. If you don't recognise any of the figures on the finance quotation then do not sign it.
Before you let your current car go I would get the dealer to confirm lead time, ideally in writing.