Rainer welcomed me at his new refurbished apartment, and it is a very clean and lovely place to stay in Vienna. Close to the metro/tram station, basically you can go around very easily. Rainer also provided me with a handwritten local map book, shows where the local would go. Exterior of the apartment building is undergoing renovation but i don't see it as a problem at all. I recommend Rainer's apartment for your vienna travel choice.