New car bought, various defects discovered

Hello Together I would need your good advice. I bought one. 750li from 2010 from private. The hook is at private purchase. Seller has also addressed three major defects in the purchase contract. 1. NightVision camera had previously rockfall, now a new one is in it and only has to be programmed. Cost point max 1h at BMW. 2. Level control/air suspension. Sensor was defective, a new one was given. Must be installed and programmed. Cost point max 1.5h at BMW. 3. Battery wa r defective . It is now renewed. Door handles/comfort access should be clamped again. Since these had previously been disconnected as a source of fault for the battery discharge. Cost point below 1h. The working hours were confirmed by BMW and overall one lies at approx. 500Eur. Now car paid and drove the next day directly to BMW to repair the above mentioned defects. BMW assumed the car as an emergency date, because by the defective level control the car is not safe. Nu 1. NightVision camera is new or used a built-in. At least without rockfall. However, completely without function. Can not only be programmed. New costs 2500,- Eur. 2. Level control sensor installed and programmed. Car regulates while driving, however, the car rises at the rear right at standing or parking. BMW wants to carry out a chassis/axle measurement here. Cost point further 200eur and then depending on what is broken Ext This is not only due to the sensor. 3. Comfort access is all jammed up again. With 2 doors the comfort access is defective. Costs about 250eur per handle. Now what would you do in such a case? Do you have any legal chances here at all? Seller is not available.