Karsten's apartment was VERY spacious and had everything we needed for a comfortable stay. He has highlighted this in his posting but just to share that it's a level 1 unit with windows facing the streets and there's no aircon. Would have preferred the freedom to open the windows or have some ventilation in the room (either fan or aircon) since we visited in summer. Location is decent and it's two stops away from the main interchange station... we highly recommend tourists to get the AB DAY pass which only costs 7 euros and allows unlimited travel for the day until 3am the next day! A single trip already costs 2 euros and you definitely need to take the train from this apartment to the must-sees in Berlin. :)