Wow, what a wonderful place to stay!
Berenice's apartment is absolutely gorgeous and has everything you need for the best stay in Vienna. The metro station into town is a 2 min walk away, and there are a couple of bus stops with routes into the centre and to the train station just around the corner.
The neighborhood has lots of lovely little cafés to enjoy coffee and cake in.
I would 100% stay here again if I came back to Vienna - it was simply perfect!