Markus's apartment was perfect. I stayed for three months and it had everything you could need for a long or short stay. U1 is a short walk, so you can get into the centre quickly and easily. Both Billa and Spar are conveniently located, and the apartment's close to Favirotenstraße which gives cafes, restaurants, and shops. The apartment is clean and modern, and equipped with all utilities one could need. Markus is very nice and helpful and he makes sure his guests are comfortable. Highly, highly recommend.