The location is everything for this studio. It’s directly across the street from the bus station, a 3 minute walk to the Metro (6) and a 10 minute walk (or less) to the Eiffel Tower. Additionally, if you stand directly at the window there is a great view of the Tower. Michel is a fantastic host - he goes out of his way to make sure you are comfortable, checks in frequently and is genuinely just a kind person who wants you to be happy. The studio has almost everything you could need for a short stay.
The studio is, as others have noted, incredibly small. The “bed” is actually a futon that, when open, blocks all of the room except directly in front of the window and the bathroom, including the door to exit. I struggle to recommend it for couples for that reason - it’s very cramped for 2 but would be perfect for a solo traveler. The only other thing to note is that you hear everything in the room - people walking up the stairs, people walking down the hall, people and traffic outside, etc. We aren’t light sleepers, but if you plan to sleep later than about 6:00am you should bring some sort of ear covers.