This apartment is absolutely lovely! It is located on a street that is close to so many attractions, METRO stops, bus lines and shops. There is even a well functioning taxi stand less than a block from the apartment. It is a quick walk to St Germain des Pres with all its wonderful shops, cafes and restaurants. It is short walk to the Luxembourg Gardens (which has an amazing playground for 6+ kids that is just 5 Euro for a family of 2 adults and one child.).
The apartment is on the 4th floor, but unless you plan to carry heavy bags up and down them several times, it is well worth the trek up once with bags! It is a quiet building with incredible natural light from all the huge windows (that also open to let in a nice cool breeze in the morning and in the evening).
The kitchen is very functional. We were able to make a simple Sunday dinner with ingredients from local shops. While the kitchen is stocked with pots, pans, bowls, utensils, etc; the host does not supply cooking ingredients, so you should plan accordingly if you plan to cook a meal. Again, this is easy to do with a market 5 mins away and a selection of butchers, bakeries and other speciality shops within a few blocks.
It took us one episode of all three family members trying to shower before heading out to realize that either short showers or staggering showers worked best to ensure everyone had enough hot water. This is not a huge deal once you know it. Especially since the ambiance of the apartment is one that makes you feel like you live in Paris.
The host Julien is so communicative. He helped us make two dinner reservations that only took reservations over the phone. We were able to make another reservation via email for the night of our arrival. When our flight was late, we sent him a message asking the best way to get to our dinner reservation and he offered to call and ask the restaurant to hold our table.