We were staying during 4 days. I was with my wife and son. Mattias was very friendly and helpful. The apartment is great: clean, cozy, with high ceilings and large windows which I liked the most. The location is just perfect. 100 m to Spree embankment with a lot of cafes, restaurants and shops. Easy walkable distance to all the first place attractions : Bundestag, Brandenburg Gate, Checkpoint Charlie, Museums Island, TV Tower. If you rent a bike you get everywhere immediately. The right place to stay to explore wonderful Berlin.