Sauber, sauber, sauber! Petra keeps the cleanest, neatest house in Berlin. And what a charming lady! She is always there to give you hints and pointers on what and where to do and go in the city. The location of the apartment was perfect for me since it is walking distance from the German language school I was going to, and also because an S-Bahn station is 2 minutes away. The bed is probably one of the best I've ever slept in. All in all, Petra's is a hands down five-star option.