Saw some questions about pickup points in front, I also rented a car from SIXT. Could someone who knows it tell me if it's convenient to pick up the car here ?

The easiest pick-up points are airports or small cities. If you are in a big city, it is often in the underground parking lot of some building, which not only causes traffic problems, but also makes it difficult to find. So, I try to pick up the car at the airport.

I will pick up the car at this address as well. I checked on the Sixt website and there are also map instructions on where to enter and exit the parking lot, so it should not be difficult to find.

Very convenient!

I can't , because I'm planning to leave London for Cambridge after picking up the car, and the car pick-up point is too far from the hotel.