Olaf's flat is wonderful. Incredibly spacious, it's quiet and peacful, clean and tidy with all the facilities you need and very comfortable beds. The location is also perfect close to Mauerpark which has a fantastic flea market on Sunday and with tram, and train transport 100m away. Alexanderplatz is 3 stops, 10 mins away. Berlin buzzes throughout the night including this area with plently of eating places open in the early hours, but it's also has a very relaxed atmosphere and feel friendly and un-rushed. I'd recommend Gorky Park restaurant for food. Olaf will provide plenty of recommendations of places to go and eat and visit. I wouldn't hestitate in staying here again.