The flat is great. Stylishly renovated and has everything you need. This is what airbnb should be but too often isn't. This is where Jan lives and not some soulless made for short term let property. Jan and Taissa were there to let us in and hand over the keys and they made us feel very welcome, even having bought a treat for the dog.
The area is a very hip neighbourhood and you don't need to leave the Kietz to eat well. If you don't know Berlin be prepared that the area is quite grimy. This might be part of it's charm.