Johannes is a great host and even welcomed us with a cake and refreshing juices once we arrived, since our visit was during summer and it was a bit hot he even managed to provide us with fan's in each room which helped a lot, Appartment is neat and has everything so basically you just come and live, cook, wash your laundry etc.
It is in a heart of Vienna so most of the most amazing places are within walking distance, metro is around 10 meters away, rooms are a good size too!
Would definitely stay there again next time.