Given the price, the apartment is a good deal, but don't expect anything great. The space is really REALLY small. The bathroom is private only in the sense that the rest of the floor can't use it at the same time as you. The walls are pretty thin and we could hear all the long conversations one of the neighbors liked to have. The bed takes up the entire space when its unfolded and its definitely not comfy - its actually really lumpy and squeaks if you move. The internet was also pretty slow.
Isabelle was a very responsive host and responded quickly to all of our questions.
The neighborhood was the best part of our stay - its great. Everything we wanted was easy walking distance and the Buttes Chaumont park is beautiful. Its also an easy commute to the rest of Paris.