They couldn't sell me an upgrade, so they gave me a lower-grade car. I booked a car with space for two 24-inch suitcases, but the Mini Cooper they provided had no trunk space. I had to pile the luggage on the back seat, increasing the risk of theft.

Overall, I'm quite satisfied. The car was in great condition, it was a new model X3 with strong power and quick acceleration (probably because the car is relatively light). The onboard GPS was very useful. Important to note: The counter staff will still offer additional paid items such as insurance and prepaid fuel. I had already purchased insurance when I rented the car, the likelihood of needing glass and tire insurance is low unless you are in an area with poor security (like an incident near my home where a car window was smashed and robbed). Generally, you don't need it, especially if you're staying in a hotel. Prepaid fuel is also unnecessary; many gas stations are cheap, and it's unlikely you will use up a full tank right when returning the car.

The desk staff had a very poor attitude.

I arrived in San Francisco already feeling exhausted. When renting the car from Thrifty, the staff told me that I must buy third-party liability insurance as required by California law. I ended up spending half an hour on the phone with the domestic rental car service. Some representatives said it wasn't necessary, while others said to pay it first and discuss later. The inconsistency in information was very poor, wasting much of my time. Ultimately, due to my firm stance, they temporarily did not charge me for the third-party liability insurance.

I rented a SUBURBAN but got a GMC, both large American SUVs. The cars were new and fully equipped. Unfortunately, no one was there to show me the features when I picked up the car, so I had to figure everything out myself. Some functions might remain unclear. The return staff were not very friendly or proactive.