Very well-located apartment: a regular bus leaves in front of the building to the Opera and Karlsplatz in central Vienna while it's a short walk to the very useful U-Bahn (metro) line 4. Neighbourhood is lively, with convenience stores, cafes, bars and restaurants, and feels safe. The flat is in a historic and atmospheric 19th century building and is well equipped, modern and comfortable, though the bed arrangement was a little odd (it's wedged in sideways at the end of a long narrow room, so that one person has to climb over the other to get in and out of bed!) Upstairs neighbour was a bit noisy during our six day visit though the flat was otherwise very quiet. We'd definitely recommend it and would stay there again. We didn't meet Markus in person, but he was really helpful, as was his sister, who checked us in,