Car Depreciation Value...plz help

I was recently rear-ended not even one month after i bought my new car (2010 Toyota Corolla) ok, i should say _gently used_ car. I had not even made my first payment on the loan. The lady responsible was cited on site, and my car was in the shop for a month and a 1/2 to the tune of close to 14k in damages. My lawyer is getting ready to settle with the insurance company (hers) and just informed me today that I would get some extra money in my pocket after all is said and done. I told him (my lawyer) from the start that I wanted to make sure that I am compensated for the diminished value of the car since if i ever decide to trade-in or pay off the loan and sell at a later date since clearly with that amount of damage is just shy of the value of the car. How can I find out exactly what kind of figures i am looking at here? Some of you may wonder why it was not just totaled out...i was originally thinking that was the case too, but I was relieved that it was not since I used my jeep as a trade in for the down payment for the Toyota and would have been left with nothing. Any and all help on this matter would be greatly appreciated. I don't even know where to start on this and more importantly how to make sure that I'm not getting the short end of the stick here when it comes to the insurance company. Thanks in advance!