We stayed 3 nights at Jakob's apartment. I RECOMMEND to everybody. The apartment is NICE, modern, spacious and very CLEAN. It was very comfortable to REACH the CITY CENTER: it takes just 3 min to reach the metro station and than in the other 10 min you're in Karlsplatz. It also takes only 40-45 min to reach the airport by metro.
Jakob was extremely polite and always replied very quickly.
Thank you, Jakob! It was great :)