I really enjoyed my stay here. Rita is an excellent host - she could not have been nicer, she made me feel at home, and I genuinely enjoyed getting to know her. The location (Kreuzberg) is excellent, especially for the price. The neighborhood is just outside of a historical/museum/downtown area (but quiet at night), very close to two train stations (one right around the corner), and walkable to museums, the concert hall, and major shopping and tourist centers.
I would definitely stay here on my next visit to Berlin!