Sofiane’s place is perfectly located, especially if you’re coming in from Gare du Nord. There is plenty to do in the local area (notably Cave des Abesses and Billili if you like food) and I felt comfortable walking home from downtown even late at night.
The flat itself is divided into a small studio-sized bedroom with a comfy sofa bed, and a kitchen/bathroom area that I didn’t use except to shower. I did notice the cleaning-product smell other reviews mentioned, but it is confined to the kitchen/bathroom area. In the bedroom, it is not at all noticeable, and that’s where you sleep, eat, chill, etc.
The apartment is up 7 flights of stairs, which could be exhausting if you have any mobility issues, but the building was quiet and friendly (you can hear some street noise in the bedroom, but it didn’t wake me up). Overall, it is a great value place and I would recommend it for a budget trip.