The Good:
-The location was very good and central for us, walking distance to most things of interest for us.
-The appartment was clean and fairly decently sized (for Paris). Having the separate bedroom from the rest of the apartment was very nice.
-It was very clean and relatively quiet (except sometimes at night we would hear people from the restaurant below, but nothing crazy). No street noise as it faces a courtyard.
-Wifi was included, in addition there was a small fridge to store snacks and a small stove/oven if wanted to cook anything, in addition to a kettle to boil water.
The Bad:
-The check-in was a disaster. We were never sent the instructions on how to enter/check-in, and the owner was not answering her phone, text messages or Air BNB messages so we sat outside for 3 hours waiting, after an overnight international flight. I would recommend in the future that if she knows people are coming, to be available and to have the correct phone number linked to the Air BNB account so that they can be reached.
-As mentioned, there are five flights of stairs to access the appartment. We are relatively fit people and not overweight, and didn't have any young children with us. So this was not really an issue (except when bringing the luggage in/out since the stairs are also very narrow). But if that could be an issue for you, keep that in mind.
-As mentioned, there is no air conditioning. This was not really an issue for us, as there is a fan and a breeze with the windows, but we were not there during any extreme heat.