While everything in my case went as planned, just sharing my experience:
Due to very short plane change, for safety I booked prepaid car for 3 hours later from scheduled landing (stupid me). Of course as expected, car was not ready (hard to imagine how they run the schedule so tight). Agent was just playing sneaky, wanting us to get more expensive car, which of course was available. In the meantime, we witnessed how he wanted to sell their insurance to somebody else... We spent some time in the airport (mainly playing table tennis) and came back to different agent. This guy was plain pleasure. We left few minutes later to our car in the garage.
Unusually, nobody is receiving and inspecting the car upon return (you just park in the garage and walk to the office), so anything can happen...