We would highly recommend staying at Alexandre's place. It is a small studio but with a clever layout making it feel spacious, and the apartment is sunny and clean. The neighborhood is fantastic--there are multiple cafés, bakeries, restaurants, bars, and a supermarket right on the block, and walking distance to many of the major sites (e.g. Louvre, Notre Dame, Monmartre). Alexandre was a splendid host--very welcoming, eager to make sure we had everything we needed and easily available by text. One thing to keep in mind is that there are six flights of stairs and no elevator, meaning this place is definitely not accessible to everyone, and a workout for most.