Stayed 1 week at Williams place in Marais, Paris. He was a fantastic host and remained contactable throughout for a couple of small questions that we had.
The location of the apartment was absolutely phenomenal. Had everything we needed nearby including grocery stores, cafe's, and restaurants. Relatively close to the metro, but we walked, used uber, or taxi most of the time since there were 3 of us.
The apartment itself was nice and quite modern. Bedrooms are downstairs. Since the floors are painted / concrete, it was extremely cold until we turned on the floor heaters for a few hours in the bedrooms. All the facilities that we needed were available.