Amazing central location, 5 minute walk to St. Stephen's Cathedral and is conveniently just above Morzinplatz bus stop for the airport too. The room was a great size and had clean utilities. My girlfriend and I stayed here from Saturday to Monday. The room is through the kitchen and feels separate from the rest of the apartment, if you want to do your own thing. There's no elevator in the building, so be prepared to walk up and down from the 4th floor. Have your torch ready on your smartphone too, as the stairwell lights are on a short timer.
Rainer was a very friendly and easy going host. This room is great for open minded people and those on weekend trips.