This flat is stylish, spacious, comfortable, with all the amenities you need. It also has a wonderful view of the Louvre Musuem and a very old, historic, Gothic church. It is in the perfect location for a Paris adventure. It is right next to 2 Metro stations (Rivoli and Pont Neuf), the Seine River (boat cruises), multiple bus stops, next to a gorgeous department store (Samaritaine), and within walking distance of Notre Dame, Saint Chappelle, the Tuileries, and much, much more. There are many shops, supermarkets, restaurants surrounding this location. Simply the perfect location.
The only thing I would caution against, if you have mobility issues, are the 4 flights of stairs. They are definitely worth the view but could be difficult to get up if you have physical limitations. Also, the bathtub is quite deep, and could be hard to get into for older folks, etc. For those that don't have any mobility issues, I HIGHLY recommend choosing this flat for your Paris stay. Even if it is slightly more expensive than some other places you might be considering, it is worth the extra money. You'll be glad you did.
Finally, Richard is a great host, he showed us around the flat and gave us information on how to use different things in the flat. He was also very helpful and responsive to messages. Thanks Richard!