My boyfriend and I stayed with Gili during the Berlin marathon as we were both taking part in the race. Gili was fantastic and responded to all my questions promptly before getting to Berlin and was on time to meet us and the flat was perfect, the kitchen small but functional as we cooked the pre race pasta dinner the night before absolutely fine and the bedroom/main room is big enough for a table to eat at. Gili made us very welcome and helpful planning how to get to the start of the race very early Sunday morning.
I highly recommend staying here not only for the flat and Gili but also for the location - it's very well placed to get around the city and wonderful places to eat/drink near by as well!