Franck's place was perfect! It was in a wonderful location in Le Marais convenient to the St. Paul Metro station on a lovely street with immediate access to many other lovely streets. The restaurant our host, Christophe, recommended - Cafe les Musees - was incredible. In fact, we had a group of gentlemen from all over Paris sitting near us who named this as one of the best (and best valued) restaurants and one of their favorites.
The apartment itself was sparkling clean and perfect for two people. The space is small, but every inch of it is used to its fullest. For example, the coffee table turns into a dining table, and two folding chairs are stored on the wall when not in use. The sofa bed is wonderfully convenient and comfortable - we're trying to figure out if we can get one in the US or if they are a Paris exclusive! The linens were nice and we slept extremely well here.
The bathroom is spacious and clean with everything you need. The only thing we realized is that there isn't a bathroom fan, so it can get a bit humid, but opening the doors to the bathroom and the main room fix this. The kitchen is well appointed and modern. There is a small and effective fan and a relatively large TV with a variety of (mostly French) channels through Freebox.
Christophe was wonderful and gave us directions to get to several places and made excellent recommendations. He was patient when we were slightly delayed in our arrival time and was helpful in getting out things upstairs. As noted by others, this is on the 4th floor. It's in a secure, lovely building with exposed beams and modern touches. We would definitely stay there again! Thank you!