We liked Sandrine's perfectly located and very clean apartment and the neighborhood is nice and safe. A very cozy size for our family of 5 and I think it is better than most in terms of overall upkeep, access stairs and corridor width to the apartment. Easy walk and directions from Gare du Nord to find the apartment and checking-in directions were clear and accurate.
With the Metro only 50m away, all the tourist sites are easily reached. Even took a walk (3km or 45 minutes) along the Canal St Martin to Marche Bastille for a Sunday stroll, passing nice cafes.
Shower was strong and the beds comfortable - sofa bed in Living not so. We spent everyday outside and didn't mind the lack of window views from the apartment. Overall I rate Sandrine's apartment a GREAT 8.5/10.