I had a wonderful time staying at Jeanne's apartment. I wasn't able to meet Jeanne as she was away for vacation, but she arranged for someone to meet me at the apartment to give me a tour, and her sister checked up on me periodically to make sure everything was going well. The apartment is situated in the perfect location, nearby a few metro stops, surrounded by plenty of adorable shops and restaurants in the Marais, and within walking distance to many museums and landmarks. The neighborhood seemed very safe (and Paris' streets are known for being well lit!), and I walked around alone after midnight a few times without feeling threatened. The room itself is very spacious and comfortable, and gets plenty of light from the window. You can hang up your clothes and really feel like you moved in! The apartment is well equipped with cooking supplies and the main living area is pleasant. There are also shopping bags and umbrellas and other useful amenities that I appreciated.
Some minor things to note: two other rooms in the apartment are also listed on Airbnb, so you may be staying with two rooms of strangers. I was very nervous as a single female traveler, but my housemates were really considerate and nice! Also the room had a weird smell that never quite went away (I think from the previous guests) and the construction going on right outside the window started every morning at 8. I still had a great time!