We had a reservation for a flat but the Host cancelled it about 10 days before we getting there, so we had to reserve Daniel's flat. We were lucky to find this option. It is actually Daniel's house and you can see it from the moment you step in, the flat feels so much warm than most of the airbnb's out there and it contains lots more of gadgets and utilities (including a very convinient 6-slot usb charger, well-cared cooking utensils and a chromecast). The beds are awesomely comfortable and there are enough blankets for very cold people.
We unfortunately reached there while the S-Bahn was repairing near us so the public transport wasn't that easy although we had a train station near.
The neighbourhood is not the best on Berlin, but there are lovely people on the building that helped us and you can find places to eat and have a beer for the cheap near there.
Finally, Daniel was very fast-responding and helped us in every issue or question we had (he even included instructions for some electrodomestics so we don't have to worry) and, as he wasn't in Berlin, asked her neighbour, Birte, to help us aswell. To make it clear, if Daniel's flat is in your budget and you want to stay in berlin, i'd go for it.