Everything went super well with our stay in Barny's apartment. Very easy check-in and the apt was really close to metro station, city center and also to the Westbanhof which is convenient if you are coming from the airport with a bus. Also it was a spacious apt (bigger than expected!) which can fit comfortably 4 people. Barny was replying immediately to any questions. The only small downside was that the apt felt a little bit cold even though there was heating.
All in all it was a really nice experience and I would definitely recommend it to anybody that wants to visit Vienna. :)