We had a nice stay at Arnaud's apartment and visited Paris for an extended weekend. The apartment is located in a lively street with many bars, bistros and restaurants and quite near to the city center. All windows point towards the inner yard though, so it's quiet.
The apartment is absolutely minimal but functional. You get exactly what you see. The bedsheets, bathroom and floor were clean, the dishes not so much. In any case, the kitchen feels like an afterthought. I wouldn't recommend the apartment if you mostly plan to cook instead of eating out.
Communication was okay but not great. The self check-in was easy and came with clear instructions. However some questions and issues we had went unanswered for a while by Arnaud. For example, we had no internet for the first two days and got no reply on how to fix it. We asked for the possibility of a late checkout a day before our departure which was promptly replied to and only then we also got an answer on how to find and manually reset the router in the house.
If you want to visit Paris for a few days and plan to explore the city by foot and only need a place to sleep, Arnaud's apartment is great. It's clean, has all the necessities and is in a great location. It's a bit on the pricey side but so is pretty much everything else in Paris.
If you plan to stay longer, have in-between rests in your apartment and want to cook your own food I would recommend to look elsewhere.