My wife and I stayed in this apartment for 3 weeks in April '22.
The location in the Marais is excellent. This is the key feature of this apartment. Close to very good restaurants, interesting shopping and several Metro stops. A great launching pad for walks throughout Paris. Pick any side street and you're likely to find something new and different to see. We were out at all hours and never felt an issues whatsoever with safety -- even when there were large political protests in the nearby Place de la Republique.
Warren is an excellent host. We arrived on our flight from the US before check in time, and he arranged for us to drop our bags at a friend's restaurant where we welcomed to Paris with a cup of coffee, some delicious food, and a smile. Warren is quick to respond and works immediately to solve problems. Someone closes the door with their keys and phone left behind? Warren can fix it. Something unusual like the circuit breaker tripping the refrigerator? Warren sends cold drinks. He's terrific.
The apartment is very comfortable and well appointed. We stayed for three weeks and felt quite at home. The pictures don't do a good job showing how much light there is in the main room. Windows on both sides let in lots of natural sunshine and we enjoyed opening the windows, getting a breeze, and enjoying the street sounds of Paris. (When the windows are closed those street sounds are not an issue.) One thing to note: the second toilet is not in the same room as the second bath. This is a minor issue - we had guests for several nights and had no difficulty-- but it's a bit of an unusual configuration. Lastly, to note that this apartment is up two flights of stairs -- what we in the US would call the third floor. There was a non-working elevator which might have been handy for carrying luggage, but the stairs were just fine for us. A little more exercise helps burn off the calories of all the good French food we ate!
All in all, an excellent apartment for a stay in Paris.