Location: Excellent in my opinion. An easy walk to the historical centre, Belvedere, Naschmarkt and other places, but also excellent tram and underground connection. Very easy to reach from the airport - take a regular train, it's much cheaper and just as fast as the so-called express train, and then one stop by underground, which is around the corner.
The building: Safe, quiet and clean.
The flat: Very well decorated and appointed, very clean. Everything was in very good condition. A lovely place to stay. Very efficient heating and hot water, excellent water pressure. The windows block out any traffic noise. I did not need the air-conditioning.
The host: Dada kindly waited for me in the apartment and responded quickly to questions. She was a lovely host.
Altogether, I would definitely stay in this flat again. I enjoyed my stay and had no complaints.