Shop around before you buy, last month i brought from a dealer  a 1 1/2 year old primastar (same van but nissan's ) with electric windows, air con, reversing sensors and  14000 miles on the clock for £6300 inc vat, still got 1 1/2 year warranty on it and its its in excellent condition. 
I know yours is brand new  but is 1 1/2 years worth nearly £7500 more.
Darren