Me and my friend had a great stay in Alexis tiny Paris appartment.
The room is small, but works totally fine for a short stay.
Please note that you'll have 0 privacy; the shower & toilet are sort of in the room (there is a little wall), so don't sleep here with your brand new lover.
It can get really damp, but if you open the windows reguraly you'll be fine.
Loved the neighbourhood! Really close to the metro station, nice restaurants and cafes.
Oh, a lot of stairs! For us it wasnt a problem, but could be for some.
Overall; perfectly fine, basic appartment for a short stay with a close friend or long time lover.