We had problem to enter in the flat, and were not able to enter before 20h, but David & Mira were great and proposed to refund the first night because of this inconvenience.
The flat is ok, a bit "cold" but the view on the courtyard is nice, the main room is great.
Renovation is very simple, and they are a lot of imperfections, the bed and the sheets are not very confortable. Kitchen appliance are also very cheap but they are enough furnitures to cook etc.
What was a real problem was the noise of the toilet, because water was constantly flowing so we had to close the door all the time.Also they are no furnitures to clean the dishes and the owners says they don't provide it and that we had to buy it, for a airbnb rental flat it make no sens, and for me it's was the first time I saw that.
If you are looking for a not expensive flat in Berlin, you can try it because this part of Spandau is great and charming but I will personally not come back.