The rental company staff were very patient and provided excellent service.

We were forced to upgrade the car model

When picking up the car, the counter staff kept pushing me to upgrade the rental model, but I refused. Then they continuously recommended insurance, and when I finally confirmed the order and made the payment, the bill was charged in USD (we picked up the car in Madrid, Spain). This was the only time we were charged in USD within Spain.

The queue was a bit long. Rental and return services were together, which was a bit chaotic.

Extremely dissatisfied with this deceitful and fraudulent car rental company. The car I was given had no logo (they intentionally gave us a problematic car that was hard to notice, probably to make us pay extra at return and buy their insurance. We already had full insurance and didn't agree). From where the logo was supposed to be, it was clear it had been missing for a long time. We didn't notice or document it until after we left. When returning the car, we provided photo evidence and timestamps, but they refused to acknowledge it and demanded compensation. Any damage to the car should have been recorded, but they still denied it. It seems like a common tactic to extort money. If renters notice the issues, they note it; if not, they get scammed. Another renter, also Chinese, faced a similar problem and was arguing with the company because they were charged for undetectable hardware issues. This is the first time I've encountered such blatant fraud from a car rental company. Never ever rent from this company at Madrid Airport. Many other options are available, avoid this one at all costs!