The first step is to document the damage as best as possible – take photographs of the car, describe the circumstances (date, time, how the damage occurred), and possibly secure testimony from other people. We then recommend that you write to your neighbour to ask them to pay for the damage. In the letter, it is advisable to quantify exactly the amount you are asking for (e.g. according to the repairer’s quotation) and set a reasonable time limit for payment.
If the neighbour refuses to pay, you can contact your insurance company (if you have accident insurance, it sometimes covers such damage) and the insurance company will then recover the damage itself. Another option is to take legal action for compensation in court. The Civil Code explicitly states that the owner of a thing has the right to compensation for damage caused by unauthorised interference with his property.