Doris' apartment is less than 10 mins walk from the main train station, and with a tram only 5 minutes from the centre of the city. The apartment was clean and well equipped and kept us cool on the hot Vienna days :)
Communication with Doris was always fast and friendly, and talking to her was very easy. She offered us suggestions of things to do on arrival. Check-in and check-out were totally easy and relaxed.
I can strongly recommend!