The host was spectacular and the apartment they provided us was very good too. It had alot of amenities that would be used on day to day basis.
The location of the apartment was great too. But beware of late night noises from bars and cafes underneath. This would only quiet down by 2 am.
Also please do note, temperatures in summer can get well beyond 35deg C and the apartment got warmed to a good 36-37 deg C while I stayed. Lack of fans or cooling system made it very difficult to live and get a good nights sleep. We were more tired when we left the City than when we arrived from Salzburg.
Other than the above two the apartment was good, with all sorts of amenities provided which makes the stay even more comfortable.
The host was super friendly too and went beyond expectations to provide details of locality and things to do during our stay in Vienna.