My sister and I had a wonderful time at Zakis and Hannos house!
We've been to Berlin several times but staying with them is very special. Their flat is perfectly located in a very nice area full of cafes, little shops and young families. The room where you sleep in, is very spacious and quiet. You definitely get a good night sleep.
Hanno, Zaki and their daughter are the perfect hosts; always there to help you and very friendly.
I would really recommend it and hope to come back soon.