remember . . .
Its a negotiation - not a fight - if you are not happy - make a case - be cool - but keep pushing - if you are going to be happy with another £400 - it shouldnt be that difficult.
State, send, copy facts and make sure they have them as well!
Also remember that ins cos are there to make a profit and will duck and dive like anyones business.
Good Luck - NEGOTIATING!!!
Khushy