We had very good stay at Verena's apartment.
Verena's place is basic but has all you need for a pleasant and convenient stay in Vienna.
It's location off the noisy center of the city, but not too far was perfect, allowing a true rest and good night sleep for people who are sensitive to noise.
The center of Vienna is just a 10 min. bus ride away (A single bus ride gets you to Schottentor, which is a hub for public transport to all parts of the city, and about 1Km or less by foot from most of the central attractions).
Verena is a great and helpful person, willing to help, advise and assist in any possible way. I would happily recommend this place to anyone.