I highly recommend staying at Julius-Tandler's place if you are planning a trip to Vienna.
Actually the apartment was clean, cozy, there was plenty of hot water, lots of supplies in the house and of course accommodation to cook something or make something to drink. He was also very helpful and polite, we had a very good communication before and during our stay. Also, the location is good overall, close to the subway station and within walking distance to town. it definitely deserved the 5 stars!