We loved our stay in this apartment, and the host was very helpful. Unfortunately, we did not get to use the balcony because it was under construction but the host made sure that we were fully aware of that beforehand. She also ensured that we knew about the stairs which were not too bad, but definitely a workout at the end of the day. Overall she was very helpful and everything went smoothly and the apartment was as expected.
The apartment itself was very clean and a lot larger than we expected from the photos which was a pleasant surprise. We didn't cook at all so I am not sure how well stocked the kitchen is. One thing that I would be aware of is that there is not technically a shower, it is a bath (which is stated in the Airbnb description anyways). I was able to stand up in it and use it as a shower; however, my 6'4" husband had to sit down in the tub to use it as a shower. It's not too inconvenient, we just don't normally take baths so showering was the best way to go.
Another thing to be aware of is that the bed and pillows are very hard. The futon/couch in the living room was softer than the bed and a little more comfortable. If you have neck or back problems I would definitely bring your own pillow.
There are lots of places to put and hang up your clothes which were very nice, and even an extra room that we didn't know about beforehand where we could put our luggage out of the way.
The location is excellent, you really cannot beat it. There are plenty of fun places within walking distance, especially food streets. You are also right near the Luxembourg Gardens, and the pantheon! The RER-B that comes from the CDG airport drops you off at a station super close so that was very convenient. There are also a couple of metro stops nearby that were easily accessible. The area is very rich and nice, so safety was never a concern. It is also tucked away on a little street off the main road and was plenty quiet. We couldn't hear anyone outside and there was no noise from the neighbors at night.