Nikola's place was great for our short 2.5 days in Paris! It was very clean, modern, and had various amenities, which was appreciated! He even left some wine, fruit, and other beverages for us. He was very responsive and helpful throughout our stay, and gave us advice and suggestions when asked.
There are many stairs to get up to the unit, which was OK for us. But, if you have a a lot of luggage or don't do stairs well, this might be an issue for you.
The unit is in a sort of square, with some kind of restaurant or something next door. During the evenings and early morning, the employees and guests were a bit loud. It was unusually warm while we were there, so we had to keep the windows open at all times. However, keeping them closed may help with the noise.

It was in a good location in Paris and was a short 20 minute walk to Notre Dame and other tourist areas. Also, was a short Uber ride from there to Arc de Triomphe, Eiffel Tower, and Montmarte.
Overall, we enjoyed our stay here and would stay again!