We spent 3 nights at Alex's place in Berlin and I can only say that our stay was perfect. The apartment is big enough for three couples with three separate rooms, fully equipped kitchen and plenty storage space. The place is very close to Kurfürstendamm, Gedächtniskirche, KDW, Zoo and Tiergarten. There are several U-BahnCard stations around and many bus lines to all parts of the city. Both the location and the apartment itself are perfect.