Our stay to Calonine's house was excelent, we were actually surprised to find such a nice place in the middle of such a wonderfull neighbourhood. We were four adults, a couple and two independent, we all had our space, the utilities and the space were enough for us. Caroline is very responsive, she gave us all the information we requested very quikly. The area is very nice, with a lot of restaurants and bars, shops and supermarkets but the apartament is very quiet, we weren't at all disturbed by any noise.
I would say that living in Montmartre in Caroline's apartment made us feel like truly Parisians for a week :)