This place is an extremely convenient place to stay when visiting Vienna. Everything is within walking distance or, if you prefer, every mode of public transportation (bus, tram, metro) is all within a 3-5 minute walk from the front door.
We arrived in Vienna at Wien Hbf and it's two stops on the Underground to Karlsplatz station and then a 2 minute walk to the apartment. Naschmarkt is probably a 3 minute walk. Walk 2 minutes to Karlsplatz station and get off one stop later at Stephansplatz station. You'll be right int the middle of Vienna! Alternatively, from the apartment walk 8-10 minutes to Stephensplatz station!
There is a BILLA market about 2 minutes south of the apartment where you can buy delicious prepared food (e.g. salads, wraps, sandwiches, etc.) in case you want to save some money on dining. Caution: one of the cashiers is really surly though (haha). Across the BILLA you'll find an Anker for some adequate bakery items and diagonal from the BILLA you'll find the Schrodinger Cafe which we discovered was a nice place for breakfast. For those with late night cravings there is a Kebab-Pizza stand across the road that is apparently open until at least 1:00 am -- probably because of the TU Wien also located across the road.
There is a an ATM (Bankomat) across from the BILLA -- you'll want some cash as surprisingly some places in Vienna are still cash-only!?
For such a convenient location we were also surprised at how quiet the location was. I guess night-life / pubs are further away as we were never awakened by merry bands of drunken revelers singing the night away as they walked by.
WiFi was good though neither cellular nor WiFi reception was available in the bedroom nearest the bathroom. Probably because of the thick wall? Not a big deal -- just sit in comfortable living room and sofa and access it there.
The washing machine in the bathroom works great! Hang your clothes dry using the drying rack found in the closet next to kitchen.
Our host Christian was very quick to respond to all our questions and also provided small touches like body wash / shampoo / hand wash for us. Much appreciated!
We highly recommend staying here if you are visiting Vienna.