Everything has been made to welcome us, Yvonne was not there but his friend was there to explain everything in the apartment.
The appartment is located 15/20 min far from the city center (subway + tramway needed), or 45 min / 1h by walk.
However, the neighborhood is not very friendly, especially at night, we were a bit disappointed about that.
But the apartment is comfortable, and it's OK to visit Vienna during a week-end.