We had a pleasant stay at Emilie’s place. The apartment was exactly as described, really clean, communication with the concierge service and key pick-up went smoothly.
We stayed during a couple of hot days (28+ degrees C) and needed to sleep with the windows open because the apartment got pretty hot. The street was very noisy, people shouting, lots of sirens, etc., until midnight. With the windows closed it was nice and quiet, but it was a trade-off between to hot or to noisy.
A good tip is to Google the neighborhood and 18th arrondissement to see if it is a fit for you to stay there.
We had a great experience with our two young children visiting Paris for a couple of days, and Emilie’s apartment was a great base for our days seeing the sights, with the Château Rouge Metro stop very nearby and Gare Du Nord at walking distance.