1. The title says, "Apartment near Montmartre". It is not true. It is nowhere close to Montmartre. It is twenty minutes walk away. I felt cheated. The Sacre Cour is twenty minutes by taxi. That is not "close". Twenty minutes by taxi you can go anywhere in Paris.
2. There is a sharp sound every few minutes in the apartment. It is probably from the boiler. Old Parisian apartments have this. If you are a heavy sleeper, then it is not a problem.
3. The neighborhood is run down, dirty, and smelly. Although there are 'hip' bars and clubs nearby for students, the apartment itself is situated in a depressing part of Paris.
4. The lift is romantic. Meaning two people has to be very intimate if they get in at the same time. :)
But it is not fair just to say the bad things. The owner was really nice enough to accommodate me for late check-in. The apartment is spacious for Paris. The place was clean.