回复：回复：碰到hit and run,怎么办？

Thank you very much. I talked with the attorney for student (I am a student) legal assistance. He wanted me to send a registered letter to the suspect and ask for damage relief from him or his insurance company (if he has one). If he denies it, I should then sue him. I am not sure if I should list the amount of money I wish to get from him in the letter or just tell him to contact me and my lawyer and then do the next step.
If I sue him, how about the chance of winning? My witness is indirect, that is to say he did not remember the suspect car's license plate number. He just saw it happened and the appearance of the driver and the car. But I saw the number clearly because he just ran away by the side of my car and he slowed down for several seconds. My wife was also sitting by me and she remembered the number, too. Can she act as a witness?
Thank you so much.