Great and very convenient.

The location for returning the car at Cologne station is not clearly marked, and the navigation on the car rental app is also incorrect. It took a lot of time to find the return location.

Very good, right inside the airport. The queue was a bit long and the efficiency was a bit low, but overall it's very impressive.

Very good

Very unexpected, AVIS is the worst car rental experience I've had in Europe and the US! I thought AVIS was a reputable and well-regulated company, but the whole process was less organized than smaller companies. First, we booked a compact automatic, knowing automatic cars are usually more expensive. When we arrived, they didn't have any automatic gasoline vehicles available and tried to charge us for upgrading to a diesel automatic (claiming it would save on fuel costs), which we initially agreed to. However, the car was shockingly dirty! The most disgusting part was the car covered in bug marks, making it hard to distinguish between bugs and scratches. For minor scratches, the AVIS staff refused to note them on the paperwork and suggested taking pictures, but distant shots couldn't capture the scratches clearly, and close shots couldn't confirm the location. We ended up having to wipe off every mark ourselves, which took over half an hour. We then requested the original gasoline automatic we booked, only to be told none were available. They refused to refund the price difference between automatic and manual, instead offering a free upgrade to a larger manual car, which we didn't need. The larger car would consume more fuel, offering no value for us. After no resolution, we called the rental platform for help. The platform couldn't resolve the issue immediately and advised us to take the car and settle the issue later. Kudos to them!!! Because we had already wasted nearly two hours with AVIS and had to reach Heidelberg by night. After returning, the rental platform compensated the unreasonable upgrade fee. Overall, I am very satisfied with the rental platform, as they truly prioritize their customers' interests. It will undoubtedly be my first choice for future overseas rentals! I just hope the platform can leverage its scale to exert more control over service providers. AVIS's dishonest behavior is a clear sign of disrespect towards Chinese customers. Globally, services usually upgrade or compensate customers for stock shortages, so disputes like this should be easier to resolve. It felt like AVIS was taking advantage of their larger presence.