When picking up the car at Düsseldorf Airport, the staff kept saying that the insurance I bought wasn't zero-deductible and strongly recommended I add coverage (costing over 300 euros). Although QEEQ had already advised against believing the rental company's upselling, I ended up buying it again (previously got tricked in Spain). This time there was indeed significant scratching. When returning the car in Switzerland, I was met by an intern who didn't know much and kept saying I rented the car in Germany and he didn't understand German. I asked him to check the system to see if my insurance would cover it, and he kept saying he didn't know. The other staff also didn't help explain it to me. In the end, I still don't know if my credit card will be charged, making me feel very uncertain even after buying expensive insurance.