Birgit is a very helpful host. As it was my first time in Vienna, Birgit also helped suggest ways to get to the apartment and offered the use of a washing machine for me to do some laundry.
In terms of location the apartment is located super close to the U1 line, so commuting to the city centre and the Vienna International Centre is very convenient. The apartment is also nice and comfortable, which was adequate for my work visit to Vienna.
Will definitely consider staying at the apartment again should I be back in Vienna.