Brice's place is perfect, exactly as described. Make sure to read the description carefully - you should only stay here if you can handle a lot of stairs and climbing into a bunk bed, and the shower stall is quite small so wouldn't be comfortable for larger people.
It's a great little place to crash after days of exploring Paris. I really liked the neighborhood (called "Goutte d'Or" if you want to look it up). It's right near Montmartre and the Sacre Coeur. There are lots of very affordable places nearby. I highly recommend Les Trois Frères around the corner, it's a lively neighborhood bar with awesome couscous. There's also a neat hipster vegan place called Cantine Le Myrha right nearby. Also if you're headed to Sacre Coeur go grab breakfast at Boulangerie Raphaëlle first.