We stayed in the apartment for four weeks, with two small children (3 and 5). Apartment is very well laid out, with two large and bright bedrooms and a kitchen that is open to the living. Washer and dryer in the apartment, working well. Amber was nice and punctual.
The location is terrific. The apartment is right on Helmholtzplatz, but because it is second floor in the second house behind the street (the Hinterhaus), it is amazingly quiet at night. Outside are all the amenities one could wish for. A small supermarket on the other side of the park, plenty of restaurants, 10 minute walk to U-Bahn (Eberswalder Str) or S-Bahn (Prenzlauer Allee). Five minute walk to Tram 12 which goes directly to the Museum Island.
Apartment location ideal for family with small kids - there are several "kid-cafe" in the immediate vicinity, as well as the "mach-mit museum" in an old church.
Can recommend without restriction!