This is a seriously wonderful place to stay in Paris! I only had the chance to meet Sophie as Joan was away, but she was a fantastic host with great communication, very helpful with directions/suggestions, and really went the extra mile (particularly in helping me with a couple of items I'd forgotten!)
It is clear they have put a lot of care into making this a lovely place to stay - the space is small but perfect and self contained, with separate entrance and fridge/kettle/microwave as described, and a bathroom with a good shower. A nice surprise was some tea and coffee already in the room, well appreciated after a delayed flight!
The area is busy and feels safe after dark, but isn't noisy, and is ideally located for public transport, with 2 metro lines nearby, including the line for Gare du Nord. Nearby is an area with good nightlife, but the immediate surroundings are calmer and have amenities like supermarket, launderette and post office.
All in all I had a great time, and would recommend it to anyone.