We had a great stay in this little apartment and it worked well for our family of three. The beds are comfy and the spot is in a really central location with two grocery stores across the street, a great bakery down the block (and Poîlane an 8 minute walk away), and the courtyard location makes it very quiet. There are some quirks but nothing big. Make sure you know how to open a Euro deadbolt, there is no AC which means you can have hot nights, and it is small so plan accordingly for storage and bags.
My one note is to be extra cautious about the door. As is the case in most European cities, this door locks automatically when you close it… which was bad for us when we did it accidentally and didn’t have the key. Luckily I had my wallet and phone (my partner did not), but a 60€ cab ride across town in rush hour to retrieve a spare, 1100€ deposit, and trip back the next day to return it was not high on my list of things to do in Paris.