Nice modern furnished flat in a good and central location in Berlin. Checking in was very simlpe and straightforward. Public transport (Bus and Ubahn) are very close and easy to get from and to Hauptbahnhof. Why the 3 stars then? Not because of an issue with the flat, but with the keys for the apartment and we couldn't get any quick help from the house manager. There were 2 key sets in the lockbox. Logically, we split the keys and 1 of our friends went for an early tour to the other end of the city and when we wanted to leave a bit later to meet them, the second key set did not work. I had to leave my wife in the flat for some hours and go get the other key set and go back to close the door and then leave. Unfortunately, as said, the house manager excused herself from bringing us another pair of keys because she was "far away from the apartment location". I lost the whole first half of my Saturday in Berlin because of this. I see this as an unfortunate and honest issue, but still a bit annoying. Besides that, all is good with the flat; you get everything you need for a nice weekend in Berlin.