Our stay at the apartment was enjoyable. The place is compact and functional, with all amenities in good working condition, and had been decorated in a stylish and eclectic fashion by Leelee, the apartment owner. The location in the 3rd arrondissement is great, with metro stations only 3 mins away and a 20-25 min walk to major landmarks such as Notre Dame, the Louvre, Center Pompidou, etc. The local area also had a ton of shops, restaurants and boulangeries. The neighborhood is very quiet, with little to no noise (expect for some construction in the building itself).
Leelee was extremely helpful and was very easily available through WhatsApp to answer any questions we had. The check-in and check-out processes were smooth and painless, as was getting to and from the apartment in a taxi. The security deposit can be paid through PayPal instead of local currency, and was returned very promptly as well.
The apartment is on the 2nd floor (3rd floor by US measures) and there is no elevator, so it may be a challenge for those with mobility issues. That being said, I traveled with my parents, who are both above 70, and they managed fine. Overall, a great experience - we will definitely visit again!