Update on this.
After a heck of a lot of arguing back and forward on email whilst I was working away and then on phone whilst at home. I have eventually made them realise my car is worth more than first valued. They have now raised vehicle value to 2695 which makes the accident value affordable to fix, therefore will no longer be a cat c and if will be getting 1510 quid for the damage to repair it myself. Considering I had a quote for 500 quid to fix it I think it's quite a good deal and makes up for some of the hassle I have had.
Thanks for all your help guys really did help me out.