Personally I'd wait for their offer, if it's less than you paid for the car then argue you'd only just baught the car so that should be the value (but they might not agree to that as people could buy cars for more than they're worth and split the profit). If you're unhappy with the offer, gather prices for cars of the same model, spec, age, mileage and condition from Autotrader/Pistonheads etc and send them the links as examples of what the actual market value is rather than the value they've taken from glasses guide or where ever. Remember to use any factory fitted extras in your favour, sat nav etc. I had to claim about 12 years ago from Admiral and managed to get more than I paid for the car as it was fairly rare for an MR2 Turbo to have TCS and cruise control (if I remember correctly, there was something fairly rare anyway) etc. Either way I wouldn't settle for less than I paid for it.