My mother and I had a lovely stay at Sebastian’s. Very clean and quiet apartment, big bathroom and an attentive and responsive host.
The public transportation is nearby and gives you quick and easy access to where you want to go. Bus 13A just in front of the house will take you to the Nascmarkt - recommendable excursion on a Saturday :)
I warmly recommend Sebastian’s place to other guests and will definitely be staying there again should I go back to Vienna!