We had a really nice stay at Sedat's apartment. Excellent location if you are coming with kids in Berlin. S- bahn station is very close and perfectly connected with all attractions. It was very cold (we stayed at mid January), but apartment was warm with heating easy to adjust.
Regarding apartment, everything looks like on the photos. (a little bit of plastering and painting wouldn't make any harm :) )
Kitchen is very good equipped with everything you might need for preparing meals. Wi fi works fine and we didn't have any problems.
Apartment was clean, but there is some space for improvement.
Anyway we spent 7 beautiful days and we can recommend Sedat's place.