When picking up the car, they told me the one I booked was too small and offered an upgrade to a brand-new Tucson. Initially, the total price they quoted was £700, which I thought was too expensive, so I declined and insisted on my original order. After some calculation, they said they could offer a discount, making the total £514. I thought it was acceptable and agreed, emphasizing that my original order was already paid for, and the final payment should be £514 minus what I already paid. They confirmed, but the final order receipt wasn't clear to me. Seeing 514 as the final number, I signed the paperwork. Later, at checkout, they said £514 was an additional charge, which was appalling as my original order was just over £300. After repeated discussions, they insisted the contract had ended and according to it, I owed £514. I've come to realize that even the British can be unscrupulous, taking advantage of the fact that Chinese people's English might not be perfect, mixing up additional charges with the total price. I'd advise future renters to be cautious of upgrade traps, even with big companies.