Such a perfect place to stay in Berlin. The flat is near several stores, several späti, restaurants, etc.
It's just above a metro station 2 stops away from Alexanderplatz where join most lines, some stops away from the center of Kreuzberg where you can eat the best "oriental" food in Berlin. Most nices places, cultural or clubbing are very close from there.
And the flat has everyrthing you need, large windows, etc. Will definitively come back there.