This is a great place in the heart of Paris which I truly recommend to everyone. Firstly, the location is fantastic. It's just a two-minute walk to the Metro, which would help for those with luggages; and a about 15 minutes walk (or two Metro stops transfer) to Chatelet; making it easy for you to access the airport RER. The apartment is located in Le Marais, a rather quaint area of Paris. While the location might not be as popular to tourists, it is a hidden gem because Le Marais is famous for local shopping (boutiques etc.), good coffee, different types of restaurants (Chinese food, health food, famous falafels, and even a famous crepe store called Le Droguerie are minutes away from the apartment), and nightlife.
Tourist highlights: Centre Pompidou, Notre Dame, Les Halles, Musee Picasso, Carnavalet Museum, the National Archive are all between 5-25 mins walk from the apartment.
Shopping: Les Halles (fashion shopping), Monoprix (groceries), local boutiques are all between 5-10 mins walk from the apartment.
The apartment itself is actually relatively large for a centre Parisian apartment. For the same price, you usually get a much smaller apartment or maybe a nicer looking studio. But my aim was to get an apartment with space and good value and that's what you'll get with Alex's place. There's cable TV (make sure to go on settings to find subtitles if this is of interest to you), good Wifi, a kitchen (needs a bit more equipment but I ended up not using much of it because of the accessibility to local food), and a separate bedroom with bathroom. The only "loudness" that I've found from the apartment was because there are many traffic outside even though it's a small street, but that's expected of Paris. Bear in mind that it IS a four flights climb to get to the apartment so I wouldn't recommend this for anyone with leg/back problems, pregnant women, etc.
Lastly, Alex was great with communication. I truly enjoyed my time here and the apartment made me love Paris even more. It's my fifth time in this great city and I'll be sure to return to Le Marais and this apartment should I get the chance to.