We had a nice stay at Quing's place. She was very generous and agreed to a late check-in, and was even kinder to let us check in much later than agreed as we encountered heavy traffic on our to Vienna. He father in law was waiting for us and he showed us the flat and told us the basics, he was kind and in a food mood despite it being nearly midnight. The flat was comfortable for our 3 night stay. I would definitively consider Quing's for our next visit to Vienna.