Round trip from Madrid to Barcelona

Good service.

Waited in line for nearly an hour, specifically said no child seat but was still charged.

The service attitude at AVIS Madrid Airport was acceptable, though not particularly enthusiastic.

We were overcharged for the young driver fee and the second driver fee. Additionally, there is still a charge of several dozen euros that we don't understand. It was a very bad car rental experience.

The process was quite convenient. They asked for the order, driver's license, passport, and notarized documents, then only inquired about additional insurance (I guessed, as my English isn't great). I declined, swiped my credit card, got the keys (which had the parking spot number), and left. Originally booked a BMW 3, but got a new Lada with only 1700 kilometers. Returning the car was also very easy; I just said 'done' to the staff (non-native speaker), they checked the car with a device, and it was fine. Back at the office, they gave me a receipt.