We had a great stay in Vienna in Ivy's and Adrian's apartment. Both of them were extremely helpful and kind. The room was decorated with love and fully equipped (+welcome present and a letter with restaurant recommendations [they were indeed really good, so trust the recommendations]). They had some guests as we were staying, but this didn't bother us at all since it wasn't loud at all. The cats were a big plus point :) For us it was also extremely important that the flat was in walking distance to almost all tourists attraction in Vienna.
We would definitely stay at Ivy's and Adrian's in the next Vienna visit!