Charlie's place is great!
Charlie was an excellent host, answering all our questions during our stay very promptly, and checking in with us to see if we were ok, during our stay. He also left a lovely welcome gift which we appreciated very much, and the small toiletries (shampoo, soap, shower cap etc) were very handy.
The apartment is in a superb location, with the wonderful Rue Des Martyrs full of great food and lovely boutiques just around the corner. Excellent cafes, restaurants etc in easy walking distance.
Lots of transport options and sites to see within easy walking distance...La Galleries Lafeyette, Moulin Rouge, Montmartre, Musée Gustav Moreau.
The description of the apartment and photos are very accurate. You do need to be extra careful if you are taller than 5'5" with some very low ceilings. I also would not recommend the apartment if you have children as the staircase without a railing could be very hazardous for small children (or if you've had too much too drink! Which is a possibility with all that great French wine!).
All in all, a great stay. Would definitely recommend.