I would highly recommend staying at Catherine's place on ile St. Louis! The building is so charming and typically Parisian. It's a 5th floor walk up, but this is very typical in Paris and shouldn't deter you from staying in this wonderful place (most Airbnb's will be a walk up). The view from the apartment is beautiful and you can look out over the Seine every morning and night. The apartment itself is very peaceful, although you can hear people sitting by the Seine, enjoying a glass of wine on hot summer nights. This doesn't go very late though. The location is great as you're right in the center of town, and you can get to everything really easily. Catherine welcomed us warmly, and it really reminded me of how Airbnb used to be----with a warm welcome from a real host, who can help you with questions and tell you a bit about the city. We really appreciated this touch from Catherine. Highly recommend!