This time I switched to a different car rental company. This one is near the airport, and there's a free shuttle bus from the terminal, which is very convenient. After arriving, I went through the rental procedures. The front desk's sales pitch was quite aggressive; I originally planned to buy local insurance, but they still tried hard to sell me a different car, which I firmly refused. In the end, they upgraded me to a Golf for free.
The rental experience was good, and returning the car was quick. My £100 deposit was refunded the next day.