Wow, wow, wow - this place is absolutely amazing. The host is an excellent and fast communicator, and so helpful. The location is perfect - you can walk absolutely anywhere you might want to go, and the surrounding neighborhood is so lively and fun, with many great places to eat, shop (cheese, bread, fruit, meat, wine, pastries, etc.), and browse. Furthermore, despite the bustle and business of the neighborhood, the flat itself is very quiet, and the bedroom is on the courtyard. (We slept well even during the Fête de la Musique!) While there is no A/C, we still kept cool even when Paris was in a heatwave (104F/40C) - we bought a small fan for the bedroom, but left it behind, so hopefully it is still there. (I'm sure that the host would have provided a fan if we had asked, but we already owned one from coming in to town from the (even hotter) countryside, so didn't bother.)
The flat itself is charmingly decorated, and very comfortable - bed, chairs, and couch alike. The kitchen is well kitted out, and perfectly arranged for a compact space. The internet is fast and reliable as well - we had to do some zoom work, and had no issues with that. Our absolute favorite part of the whole wonderful package, though, was the balcony - spacious, surrounded by plants, with a sofa and a dining table, looking out over the rooftops. We spent many happy hours there. I highly recommended this place, 100%!