Osnat's appartment is excellent. It was very clean, cosy and also exactly as described. It is very close (7 minutes walk) to the nearest metro-train station so makes it easily approachable from the city's airport. Also it is 3 stations away from the city center (U1 metro line).
Osnat responded to every question we had quickly and to the point. Even though we haven't met Osnat in person we can easily recommend her as a host for your staying at Vienna.
Thanks again Osnat!