This apartment is in an amazing location, close to the Louvre, the Musée d'Orsay, Notre Dame, etc. (We even walked to the Eiffel Tower and Sacré-Cœur.) A large Monoprix grocery store is about four minutes away. The apartment is very clean and has nice features, including comfortable furniture, a variety of dishes, and great appliances. There is a trash and recycling area on the ground floor, which is convenient.
As others have mentioned, if you have mobility issues, this would not be a good choice. There are about 85 stairs (spiral style) up to the apartment. Travel light! Inside the apartment, the flight of stairs up to the bedroom does not have a handrail. We were very disappointed to find that the advertised second bathroom was sealed off. From other reviews, this has been an ongoing problem. The owner should update the listing to reflect reality. Also, there was sometimes a smell of sewer gas in the apartment. I believe it comes from the shower stall. If you keep the shower closed, it's bearable.