Christian's apartment is well appointed and modern, very close to the center of Vienna. Everything went very smoothly when we coordinated our arrival, he gave us the keys to the apartment and took us to see the view from the top of the Sofitel nearby - it was a bit foggy so we didn't stick around.
Everything was well organized in the apartment, it is very spacious and comfy for a city getaway. And you have Vienna on your doorstep! What more can you ask for?