1. The breakdown and origins of each fee were unclear. I never received the contract after picking up the car. They said they'd email it in 3-4 hours, but I never got it. The detailed invoice was only provided when returning the car, and it wasn't clear enough; 2. We booked a Volkswagen, but they gave us a CUPRA at the same price, despite having reserved the Volkswagen well in advance and arriving on time. The car rental company switched our car under various pretexts, which was unreasonable and resulted in extra costs; 4. On the return day, the car was fully refueled and had no issues, yet the invoice included a full tank refueling charge... 5. We only agreed to the full insurance, an additional driver fee, and the cross-border fee for driving out of Germany. No other charges should have been applied. Besides the 5200 RMB for the rental, my credit card was overcharged by an additional 8000 RMB, with excessive extra fees.