We thoroughly enjoyed our stay in David's apartment. It is just on the Left Bank/Latin Quarter, one block from Notre Dame and literally across the street from the river. The Ste Michel RER line has an elevator access just 1/2 block from the apartment. As the others have said, the bedroom is located in the center part of the apartment away from street noise below. From the living room, you can hear the restaurants and bars below but if you have white noise in the background it should not be a concern. The beds are comfortable, the flat is clean and in great condition. The dishwasher, washer/dryer worked well, which was nice to have as we wrapped up our 2 week trip.
Perhaps the best part of our stay was David's hospitality. He reached out to us in advance to understand our travel schedule, and was at the flat when we arrived from the airport on the train. He provided us with excellent recommendations for restaurants and markets. And we really appreciated the groceries he stocked for our arrival. If you enjoy staying in the middle Latin Quarter, you will love David's place.