Was the 5th offer for my Vectra when some arse when in the back of that. Went from £2200 to £4100. I had to send them autotrader / ebay / piston head printouts to prove that it was worth ~£4500. + all the service history + all the receipts + the alarm installation certificate. Remember they are now paying for storage and they won't like that
As for getting it back and repairing it - remember it will most likely be a Cat D (or C) insurance write off so it will be harder to sell and cost more to insure.
Shame really, genuinely not your fault and I can tell you like your car
I dislike insurance companies.