Just finished our stay in fred's penthouse apartment in the heart of pigalle. You are within walking distance to montmatre area and surrounded by 3 subway stations. It is very easy to get around to all of the sites in paris from fred's apartment. The apartment is nicer than in the pictures and you get a real feel for Parisienne life. This is not a quiet neighborhood, and fairly noisy outside all hours of the nught and day.
Fred was a wonderful host, provided us everything we needed to make our stay comfortable. The biggest issue we had was not knowing where the light switch was in the lobby downstairs. Also the elevator did not always work for us and we ended up having to walk all 5 flights of stairs in the dark one night.