The apartment is nice and we got a special experience that we wouldn’t have had if we stayed in a hotel. This we knew in advance, but I think all guests should be notified that the apartment is on the 5th floor (or 4th floor in Austrian counting) and there is no elevator so guests have to climb a fair amount of stairs. The stairs, though, make the apartment appear quite historical and is a necessary experience in Vienna. We also had some trouble with opening the door properly so asking in advance might be a good idea.