Thank you

Hi I had an accident two days ago. It was my fault but the damage to the other car was minor so I suggested I could pay for it. Today the driver called me and said that he can have the car repaired for 150 pounds. It suits me, but is it legal and how can I protect myself against future claims ( medical claims ). Is there any form or a statement template I can use? ( Obviously it was a simple collision where speed of the both cars was very low and there is no way anybody could suffer any injuries ).