I am sure they have to to price it with the VAT on first then take the £3500 off so it’s approx £700 more just a guess
I posted this elsewhere, so apologies of you have already seen it.
I don't believe there is any cost difference. I saved my previous order agreements and I get no difference other than the £3500 gov grant.
(their *, words and figures, cut and pasted):
Original
Price excluding VAT £46,350.00 Price Including VAT £55,620.00* VAT (20%) £9,270.00 Price Including VAT £55,620.00 *Price
includes the UK Government Plug-In Grant of £3,500.
Revised
Price excluding VAT £49,266.67 Price Including VAT £59,120.00* VAT (20%) £9,853.33 Price Including VAT £59,120.00 *Price
excludes the UK Government Plug-In Grant of £3,500.
Difference between £55620 and £59120 is, tada £3500, the amount of the government grant. The difference between the price ex VAT prices is,£2916.67, or near as, £3500 incl. VAT.