Two of my friends and I stayed at Filip's place for a night but I can say that when we go back, his place would be in our list to consider. Although we did not have the chance to meet him, I felt his hospitality through his messages. His place was very accessible to a lot of beautiful musesums, landmarks, parks around the center of Vienna. A tram stop is just 1 to 2 minutes away from his place. Although the building was old, it had a nice Baroque atmosphere inside. Just consider though if you are packing a huge suitcase, there are no lifts and there is no light in the hallway in in the ground floor.