Park accident, how am I acting smarter?

Hello together, on Saturday morning the race management is standing in front of my door with the indication that someone was driving against my parked car. My car is old and rather degraded. The TÜV runs off at the end of the year and I have my doubts as to whether this will be Christmas again. The damage was also quite small. In the rinzip only the mirror glass jumped. I don’t mind that and at the end of the year the question arises anyway, whether the car will get away. On Sunday then the lady was there, d he went against my car and told me the police file number and her phone number and address. She then said that her insurance would contact me, but first she would like to see if she could settle the damage jnciht out of private pocket more cheaply. Can she certainly, but what should I think of it? I now thought that this would be so that I had a nice estimate made by the dealer and send her insurance, whereupon Is that working, or what does it look like? Do I have to accept this when it offers me “100€ and forget”? Am I really obliged to have the mirror renewed in the specialist workshop? This will not be in proportion to the value of the car. I estimate the car to be 800€ and the mirror costs 150€ without installation at VW… Thanks for tips!!