Sarah is a very nice host, I felt very welcomed by her when I arrived. She equipped me with everything I needed and more. The apartment itself is very beautiful arranged and with an eye for the detail. I also really liked the guides of different areas of Berlin with recommendations of different places.
Over the street there is an organic supermarket which also has a small café/restaurant inside. There you can eat rather cheap high quality food or take it with you.
I would love to stay at Sarah's apartment another time and totally can recommend the stay.