We had a great stay at Sven's place. The location was perfect for us - 10 minute walk to Brandenburg gate, Natural History Museum (with metro stop). Lots of restaurants and amenities within a short walk.
We were two couples and had plenty of space. There are two notes that future guests should be aware of - there is no lift so stairs to the second (we would call it the third) floor need to be navigated) and there is only one toilet so if you fill it to the capacity of 8 guests there may be a bit of a queue! We had not problem with either of those issues.
We did have a slight glitch with the electronic key fobs but Sven was very attentive and available and came to the place on short notice on a Saturday to sort it out. That was very much appreciated.
We would definitely return!