I spent 2 week at Mathias' place and it was perfect: everything is as on the pictures, the bed can look small (for one persone) but you can just open it and then it's really big and confortable. The tram and bus stations are near (3 min walking or 30 sec running) and going home from anywhere in Berlin is very easy, also at night. Mathias is very kind, funny, respectfull and helpfull. I would recomend him, for sure!