The flat is large, bright and clean, exactly as it was described. There is a balcony, perfect to have breakfast on ! It has every equipment you need, and it is located in a very quiet area.
Anna and Sasha (the hosts) both answer very quickly and speak a perfect english. We had the chance to meet Sasha and not only is he very nice, but he is also very helpful to solve problems and deals with them very fairly. He was keen to make our stay as comfortable as possible.
In a nutshell, I do recommand this place for a stay in Berlin, especially for a family or a group of friends.