I didn't meet Harriet in person but check in instructions were perfect and Harriet answered all my questions very quickly.
The apartment is huge, very big and beautiful and very well equipped with all you need for a short or long holiday. It's also very quiet, I slept very good. The position is great, you can take tram n. 37 to go to city centre, tram D to Belvedere Castle and bus 10A to go directly to Schonnbrun. All reachable in 30 minutes more or less. Billa supermarket is only 400 metres away and in the area there are good and cheap restaurants.
I highly recommend this apartment!