Regardless of whether your accident with the rental car occurs abroad or in Germany: First you should secure the scene of the accident and, if necessary, notify the emergency services.
If there is another road user involved in the accident, call the police and have them make a report. You will normally find an accident report for this case in your rental car. You should fill this out together with the other road user involved in the accident and the police.
If no other car is involved in the accident and you have hit an obstacle, for example, you should still notify the police as a precaution so that they can draw up an accident report for you.
If the police do not come to the scene of the accident because the damage is too small, it is best to drive to the nearest police station and have the accident recorded there. The accident report is very important for you, as otherwise the insurance cover for your rental car is at risk.
You should also inform your on-site rental company immediately. If necessary, they will organise a replacement rental car for you in exchange for the accident vehicle. When returning the damaged car, have the rental company issue and sign a damage report. Also make sure that you keep your rental agreement and proof of payment of the deposit and excess. We need these documents to claim your rental car after your return.