Staying a Francesca's place was truly lovely. Being just a couple of minutes from M Gobelins made it super easy to walk or take the metro into the center. It's a studio with a single bed so it's only suitable for one person. But, it was very comfy for just me. It's an old apartment so naturally you can hear a lot when neighbors are active, but it always quieted down at night and I never had trouble sleeping. It was very clean and Francesca greeted me quite late in the evening and made herself available to answer any questions during my stay.
I would certainly recommend this place for your trip to Paris! :)