We would recommend Augustins appartment to every group or large family visiting Berlin. The location is perfect: close to various big sights, restaurants, shops etc. You don't get the idea you are in the city center as there is no noise at night, allowing you to sleep peacefully.
The appartment is spacious and fulfilled our needs. Kitchen is well equipped and the bathroom is convenient. Large towels and comfortable beds. Beds aren't very long though and therefore not suitable for very tall sleepers (us Dutchies are tall).
Communication with Augustin was great. He replies very soon and was there to check us in upon arrival and explain us all the necessary details.
Many thanks for providing us with this appartment during our stay (3 nights) in Berlin!