Room is located within the Charlottenburg neighbourhood of Berlin, and is very close to a subway and S-Bahn/train station. Bus to Tegel Airport is also only a five minute walk away. Wilmersdorfer Str., a busy pedestrian street littered with shops and supermarkets, is just around the corner. Several interesting restaurants, bars and cafés are within a short walking distance.
Mirko is a nice and attentive host who awaited me even after 11 pm. He has been living there for many years, so he'll be happy to help you out with some useful recommendations.
The railroad tracks are nearby, so if your sleep is light don't forget a set of earplugs. With the window closed it should be fine.
All in all, it was a pleasant experience and I would definitely return there.
Vielen Dank, Mirko !