I agree with STL...my old A4 got rear-ended by a Silverado when my son was driving into town. Chain reaction, the car then hit the F150 with a large tow hitch he was following.
Banged up front and back...totaled. When my insurance rep called me, he made his first offer...I then told him to sharpen his pencil and listed what's been done to the car/maintenance/etc. He bumped the offer up immediately to my satisfaction.
Coincidentally I was planning to sell the car anyway, and the amount I got from insurance was equal to what I was planning to ask for the car...pretty lucky from that standpoint.
As stated, have your data ready to provide to the rep.
Good luck sir.