Dash cam.

 Get and use a dash-cam. It was indispensable in our wreck. The guy tried to say Nat ran the stop sign. The cop tried to say we were at the wrong intersection. The other guy's insurance company sent six letters saying they would not pay, all on the same day. That was when I knew I had them. The officer would not take the card from the dash cam. I asked him if he wanted it and he said "no". I thought that was strange, but it would have meant it was officially in evidence and a far greater headache for him.. I gave it to my insurance company and they used it in arbitration. It over-ruled the police report. It over-ruled the other guy's statement. It overruled the other insurance company. We won arbitration. Our insurance person said that is a pretty rare thing in a hotly disputed case.