Lena's description of her apartment is spot-on. It's quiet, comfortable and safe. The location of the apartment is perfect for exploring the city by day and coming "home" to a cool district where there's lots going on with so many choices for places to eat and drink. If you happen to be a vegetarian, prepare to have your mind blown by the fact that you can chose from the whole menu in many restaurants!
The next time I visit Berlin, I'll try to stay here again.