Our party of 3 recently had the fortune of being hosted by Erik at his place in Mitte, Berlin.
For starters, the photographs don't do this place justice. It is much larger than the pictures make it look, and easily accommodated the three of us. It is spotless and spacious.
Erik was very responsive during check-in, and spent some time showing us around his home. He was also kind enough to offer some suggestions for attractions in Berlin.
The neighborhood is really cool (like Williamsburg but not filled with hipsters), and food and drinks were both incredibly cheap by NYC standards. We were walking distance (<15 minutes) from a ton of tourist attractions and restaurants, and literally steps away from public transit.
If we ever find ourselves in Berlin again we will definitely seek this place out!