Katja's place was wonderful! The apartment was very cool with quirky-urban furnishings and the balcony was an extra special treat. The neighborhood was fantastic - lots of cute and cozy bars, cafes and restaurants, but overall very clean and not loud. The only minor thing was that in the house the walls were a bit thin, so you might want to bring earplugs if you're a very light sleeper, but it didn't bother us. I would very much recommend Katja's place, if you're looking for a cool and cozy place in a superb neighborhood in Berlin.