I stayed at Katrin's place for six weeks during my research stay at FU. It is maybe a 8-10 minute walk to he Dahlem Ubahn stop and FU. The guest rooms are on the top floor and there is a nice bathroom and kitchenette. The room was spacious and had a nice large desk. Katrin and Fritjof were always reachable and addressed any need or questions I had. I hope when I return to Berlin that I can stay here again!