Armin's apartment is an excellent choice. It is spacious, bright, quiet, and clean and with a kitchen space that is a well-stocked and a pleasure to use. The large living room is great for working, reading, and for doing yoga and stretching. The whole neighborhood is quiet, but it is close to lots of life because of the convenient metro system. In only 5 minutes from the apartment you are at Line 3 of the U-Bahn, 1 stop from a transfer to the very central Line 2 which services a host of sights (e.g. KaDeWe, the Zoo, Schloss Charlottenburg, Potsdamer Platz, Gendarmen Market, etc). There is a small supermarket only a few minutes walk away too. I spent five very comfortable and pleasant nights here and recommend it highly. I never met Armin or Suzette, but communication via email and phone was always quick and responsive.