Overall, this was an exceptionally good experience. Mark was clear and responsive and even followed up after our stay asking how it was. We are quite pleased. We stayed 4 nights, and during that time we found mostly pros and a few small cons:
Pros:
--wonderful location 1/2 block from a major metro stop (Chatelet-Les-Halles entrance 7 at Rue du Jour) made getting around the city super easy.
--lots of cafes nearby -- and the supermarket (G20) only a block away
--the large windows open up on a church and a courtyard for nice views and fresh air -- a lovely spot!
--the flat was quite clean, and there was room in the wardrobe for our clothes
--the bed and sofa were quite comfortable
--the wifi was strong/good
--great shower!
Cons:
--it's on the top floor of a very charming old building, which means the stairs are very narrow, very step, curving, and uneven/tilted. It's mentioned in the listing, so it wasn't a surprise, but just be aware that the stairs are very difficult to navigate, especially if you have luggage. It's part of the charm, but be careful!
--the lighting was all area/spot lighting and the light above the sink in the bathroom didn't work, so it was difficult to apply makeup, see into the wardrobe, or read while on the couch at night. This is a small thing, but worth noting if you need good lighting.
--the kitchen is truly tiny. Again, this wasn't a surprise, but it's worth, but it's too small to do any real cooking. We did manage to use the one small pot to make some pasta one night, but it's better suited for light/cold/quick meals.
--the sofa doubles as a bed, but other than a single blanket in the closet, there was no bedding for the sofa that we could find. It was warm and my daughter was fine just sleeping on the sofa with the blanket, but we thought it odd that there was no bedding. The bed itself had bedding, though, so maybe bedding for the sofa needs to be requested in advance.
--the washer/dryer unit isn't what Americans are used to, and it's quite complicated to try and figure out how to use it (after 4 drying cycles the clothes were still wet, and we have no idea why!). If you plan to use the washer, plan enough time for clothes to air-dry. Having instructions on how to use the washer/dryer would have been great! (Again, not a problem with the flat -- just a snag we ran into.)
The "cons" here are more items of note than they were really problems. The place was wonderful and we had a lovely time!