We had a great time in Paris while staying at Celine's place. Check-in was super easy and Celine was very communicative throughout the entire process, which we appreciated. The apartment is also in a great location, within walking distance from most sites and museums.
While the unit was comfortable, it was definitely smaller than we anticipated. It sits on the ground floor with windows facing a courtyard so don't expect a whole lot of natural light. Lastly, for any light sleepers or those sensitive to mattresses, the bed was not the most comfortable.
Either way we would recommend staying here when traveling to Paris.