I booked a car on the Zuzuche website and paid the full amount. However, when I got to the store, there was no car available. They took advantage of my lack of language skills (I only speak Chinese and a few words of English) and asked me to pay an additional 531.44 euros under the guise of an upgrade. After swiping my card, I felt something was wrong (fortunately, I hadn't signed their receipt) and immediately called Zuzuche to correct the order. But I still don't know if the money that AVIS charged me can be refunded, even though the Zuzuche agent said it would be based on the actual payment (I added an extra day to my reservation).