Kerstin was a great host. She was there when we arrived and gave us recommendations of places to go. The apartment is great and very well connected to the transport. We pretty much walked everywhere and there are shops and restaurants within walking distance. We went in a group of 7 and had the two apartments which was perfect for us. There is plenty of space to socialise and eat together. The bedrooms of one of the apartments overlooks a courtyard where occasionally people would talk late at night so may be worth taking ear plugs but on the whole it was a perfect place to have as a base in Berlin.