We had an excellent stay at Stefan's place. The apartment itself is beautiful, very spacious and bright, high quality furnishings and a brand new, well-appointed kitchen. Stefan himself was very easy to communicate with and responded quickly to our questions. And the location is tough to beat -- one of the best neighbourhoods in Berlin, with tons of good places to eat and drink within a few minutes' walk, U-Bahn around the corner, grocery store just on the other side of the square. Highly recommended!