The flat is small but has everything you need for a small stay in Paris. It has central heating, which was very handy because of the cold outside (-1ºC).
It is in a central part of the city. Very close to the metro station and within walking distance to some highlights of Paris like Sacre Coer, Moulin Rouge and even Passage Jouffroy and the other galleries.
Sylvia was easily reachable except for the last day when we had to wait 30 min after the agreed time to check out... Despite this I still recommend this place for a short stay in Paris.