Caroline's flat is an excellent choice for a longer stay in Paris. It's in a quieter neighborhood in the 19th which is a nice retreat after spending the day time in busier areas of the city. The flat is close to the famous cemetery, Belleville Park, an amazing art book store, and a metro stop.
After staying in several Airbnb's in France, Caroline's flat has two hugely underrated amenities: a very firm, comfortable couch for lounging after a long day of sightseeing and a shower head mount so that you take a hands-free hot shower.
The flat is not large, but the floor plan is compartmentalized in a way that makes it feel like plenty of space for two people.