This place is awesome. We stayed a week with our two kids (9 and 13) and they loved it. They each had their own room on the lower level (we didn’t use the 4th room). Upstairs is the main hang out area and kitchen. Washer dryer on lower level was super helpful too.
This neighborhood is our favorite in all of Paris - we have stayed in and around this area before. I wish we’d found this before. So central it’s crazy. Steps from St Germain and right in Rue de Buci. It’s a narrow stairwell up with no lift - didn’t matter at all to us. Would highly recommend.