Great place to stay which is near city transportation and plenty of restaurants nearby. Can get noisy in the warm weather if you have to open the windows in the living/dining/kitchen area with people walking by constantly, but if the windows are closed it is pretty quite. There is no air conditioning. Make sure to bring your own hair shampoo/conditioner along with laundry detergent as non is supplied. Pillows are very soft and don't really give any head or neck support. Luckily we brought my own pillows. Could not understand how to use the convection/microwave at all even though there is a small manual. Would have been nice to get simple English instructions posted on top of the microwave.
Sabine is a great host who responds to any questions by email quickly.
All in all, a great place to stay for our 1 week in Berlin.