The flat is as the pictures show, very clean and well equipped for a long stay in Berlin. It's located in a very calm and quiet neighborhood and near a park.
It's well served by public transport. You are at 5min by walk to tram 21 or 15min by walk at S Bahn Karlshorst (S3) and Hegemeistereweg for tram M17, 37, or 27.
Nice place to stay for a long trip in Berlin. Great host, good communication, I recommend!