I would definitely have clearer instructions on locating the apartment. There should probably be pictures of the elevator & also the the flights of stairs. It would also be helpful to have a little handbook for how to use the apartment especially the bathroom/shower. Also, the buttons you need to press to get out of the apartment building because if there were not regular tenants, I would not know how to open the the gate to get out of the complex.
Overall, it was still a great place, great price, & great location. I am pleased with how easy to communicate it was with the host & regardless of the mishap with the check-in, I do appreciate them letting me leave my luggage before the actual check-in time. The apartment is close to buses & metros that take you directly to the heart of the city & other monuments. There are little gems tucked around the apartment location to eat & buy food. I would recommend their spot for a solo traveler who doesn't need much space & just needs a place to stay and be comfortable. One thing to let travelers know is about the harsh winds at night which may keep people up.
Overall, this was a great stay & solo trip to Paris. Would recommend to folks especially for the price. Also, there is a restaurant called "Jourdain" that's a 5 minute walk from the apartment which I recommend 1000x!!!