It is a beautiful appartment with a lot of space, completely fit to stay with 4 people or as we did with 2 people liking there own room and bathroom. It is also possible to sit outside in sunshine for the whole day. From this spot you can bike everywhere in Berlin within half an hour. When you have a meeting or conference in Estell Hotel it is very well located and within reach by walking (15 min) or biking (less than 5 min).
Also convenient: the bus from/to Berlin-Schoneberg is around the corner.