This place is located in the center of Berlin with easy acces to all highlights using public transportation right in front of the appartment. A few 100 meters further you can take a direct bus towards the Tegel airport as well.
Arnd is very friendly and even helped me out with drying my clothes as I was suddenly struck by a 'tropical' shower.
It was quite hot in summer without airco. The private bathroom is complete and clean. Unfortunately when I was here a new window was just installed without blinds so I had to put up a blanked but it should be fixed soon.
All-in-all it was a good experience with great value for the money. I would recommend Arnds place to most people!