Avoid this car rental company!!! They force you to buy insurance!! When we picked up the car, the staff kept pushing for full insurance despite our clear refusals. The road from Kayseri to Goreme is in good condition. Even after we declined the full insurance, our credit card was still charged 1123.68 lira without our consent. The car rental company recorded our credit card details manually without using a POS machine (which is very concerning). Only after we left did we notice the charge. We later found out it was for the forced full insurance.
When returning the car, there were no staff members in the parking lot. No one answered the phone either. After waiting for some time, they came only when other customers arrived to rent cars.

There is still insurance promotion, just say 'No' if you don't want it.

The process was smooth, but the refund wasn't very straightforward.

I booked a VOLVO S60, and the order explicitly stated S60. However, when we got to the counter, they informed us that there was no S60 available and gave us a V40 instead. The car was quite average too. To make matters worse, when returning the car, we missed a gas station, and the fuel tank was only half full. For that half tank of V40 diesel, AVIS charged us 300 lira, almost 700 RMB, which is roughly 23 RMB per liter of diesel—a ridiculously high price. After a tough negotiation, we managed to get it down to 250 lira. Overall, I'm very dissatisfied with AVIS. I paid for a mid-sized car but got a compact car experience. Fortunately, we only had 3 people traveling; if there were 5, the trip would have been impossible. Additionally, being overcharged when returning the car was aggravating. If I weren't afraid of missing my flight, I would definitely have gone to find a gas station before returning the car. Choosing AVIS initially seemed like a good idea because of its reputed service and reliability, but it turned out no better than any other company, if not worse. More money spent for poor service.

Upon arrival, the car I booked was not available, and I was asked to pay extra for an upgrade. I was very dissatisfied after refusing.