In our home country, we took the same car with the same people and luggage to the airport, but the staff here insisted that the Mercedes C-class couldn't fit our luggage and asked us to pay for an upgrade to an Audi A4 wagon. Coincidentally, another customer nearby was also asked to upgrade. It seems the reviews about forced upgrades are true. We were in a hurry, so we had to upgrade. Fortunately, the A4 was a diesel car, as I hoped, and had only 3277 kilometers, almost brand new. When returning the car, the staff inspected it very carefully, noticing a tiny chip on the windshield caused by a small stone. Thankfully, we had full insurance. I checked the windshields of a few nearby cars and saw many such tiny chips; the company considers them as damage. I suggest getting full insurance when renting a car. Overall, the car was fine, but after driving 1000 kilometers, it indicated that it needed one liter of oil, quite similar to domestic Audi cars needing oil for long trips.