also, any tips on the pick up and drop off?

we're landing in TXL but I'm taking a taxi 5 min away to save myself $200. (its a 40 day rental). I was thinking of going to the txl desk and asking them to confirm that they do have a car for my waiting at the city location. Otherwise, I understand they would have to give me a car from their airport location?

Just curious as to what to look out for and what they have tried to scam renters on. Pre-fill, etc.. that kind of stuff. I've already read enough horror stories that I'm going to record the whole pickup procedure and have a detailed look on the car for existing damage