We spent 5 days in Berlin on a family trip, with two parents and three teenagers. The parents slept in one of the front bedrooms, one of the teens in the other. The second teen was in the back bedroom, and the third slept in the loft above the kitchen. The apartment has enough beds to sleep even more people.
The apartment is located near a U-Bahn station to the north, S-Bahn to the east, and several bus stops nearby. We did not have a car, we took public transit with at most one change of train to get anywhere we wanted. There are a number of restaurants and several biomarkt in easy walking distance.