We had a fantastic time staying at Celly's flat and had a great time in Berlin. The flat really does live up to the pictures and is a really nice place to be. The space is absolutely huge too so you won't be wanting for room.
It is a ground floor flat with just a single door which opens out onto the street but the area feels very safe.
There's not a huge number of extras like recommendations on where to go or instructions for the flat but Celly was very speedy in replying to us.
Would absolutely recommend!