Chris is so nice and available, he always answers quickly. He also has some plans of the city prepared and directions to the cheapest closest parking lot printed out.
His apartment is very clean and functional. It is located right in front on the subway station (line U4) which is absolutely great. You would find everything you need to cook and eat, also slippers, towels, shampoo and shower gel.
Sometimes it smells a bit tobacco because of the neighbours who smoke in the building, and the noise in the corridor is quite loud, but you won't hear the noise on the street even though there is a lot a traffic around.
There is no air conditioner but there is a fan which should be enough. The bed is comfortable. Be careful though there is very little hot water, you won't be able to take to showers in a span of a few hours.
The apartment might be a bit small for two people, it is like a student studio but we managed to live in it very well by being a couple. And we strongly recommend Chris' apartment if you want to come to Vienna for a few days on your own or in couple :)