We were a group of 4 and we only stayed in Berlin for one night so we could explore the city a little on our way to Poland. We booked Martin's place mainly because of all the great feedback from previous travellers. And our experience was no different!
It was a great place, looked just like on the pictures, very clean, cozy, and just what we needed. The location is just amazing! Walking distance to postdamer platz, right in front of the U bahn, so really really handy!
And Martin was a great host! Well prepared with maps and recommendations, very easy going, and was super easy to get in touch with! So I would recommend this place to anyone.
Definitely coming back to Berlin in the summer and hopefully staying at the same place again :)