Christian's apartment was great for the 4 days my friends and I spent in Berlin. It's sunny and spacious and has the cozy air of a real home to it because Christian himself lives there throughout the year, so you get a more authentic feel of how life in Berlin really is like. I personally appreciate this kind of thing but if you prefer more impersonal, hotel-like apartments this may not be the place for you.
The flat was clean and tidy and has a nice balcony, where you can have lunch or dinner in summer and veeeeery comfortable beds which was a relief after several nights sleeping on trains and hostal beds :) It is located in a nice and quiet area and has great connections by tram but you have to walk a little longer to get the u-bahn (12min) or s-bahn (20 min).
Christian has been very responsive and friendly both before our arrival and during our stay, which we really appreciate! Thank you so much, Christian, we had a wonderful stay!