Honestly, this is a fantastic place for an extended stay (3+ weeks), close from everything and very accessible from public transport. Would recommend in a heartbeat to anyone who wants to visit Vienna while also having the feeling of being at home :) I sadly couldn't meet Gunter in person, however I can say that he answers very quickly to any message and is very available.
Overall, we had a fantastic vacation, and this in part due to having a great place to stay that felt a bit like home :)