Rainer was very kind to us all the time. We've changed check in time due to the delay of train, but he still welcomed us with friendly tips about the flat and area around. We had best Austrian food at the restaurant he recommended. He even helped us pulling our heaviest luggage up the stairs. The flat is comfy and neat, much spacious than it looks in picture.
As I stayed in Rainer's flat for 10 days, I would totally recommend here for your perfect trip to Vienna. The area is not at all touristic, but it's only 10 minutes walk to center of the city. I already miss the days in Vienna!