My parents, baby and I used this as a base for our exploration of Berlin over 3 nights. Overall our stay was good, the location allowed for multiple public transport options and the kitchen/bathroom had everything you'd expect, as well as a few bits and bobs left over from previous tenants (particularly useful in terms of toiletries if you can't bring your own!).
My only complaint is with the quality of the bed/s. The main bed mattress is very soft and squeaky (a problem in a lot of airbnbs) and the sofa bed has a head incline on it which made sleeping rather awkward, and I woke up with a sore neck every morning. The duvets and blankets were all lovely so it's really only the sleep surfaces which are at fault here. Unless they were changed we probably wouldn't stay here again. As with (almost)all German properties, they use the giant soft square pillows with no neck support so bring your own if that's important to you!