Berenice's place is very nice and well-located. It is a modest-sized apartment in the heart of Paris (I could walk to the Louvre in about 20 minutes and in the Eiffel Tower in 30).
You share the space with her on a small bed off to the side, so be aware of that if you have any issues sleeping in the "same room" as a stranger. That said, Berenice gives you your space and is not intrusive, and is quite a heavy sleeper, so neither bothers the other person overnight.
The bathroom is small and functional, as is the kitchen, but she does have a few nice accessories like a microwave, stovetop (for one) and coffee maker - she will make you coffee every morning if you ask politely :)
I must also admit that during my stay there was an issue with a mouse that was able to get into the apartment. I am a light sleeper, so when it was searching around, it sometimes woke me up. The mouse never came near my things, so I wasn't bothered by it other than occasionally hearing it. If you are sensitive to that sort of thing however, I recommend checking with Berenice when booking to make sure it won't be an issue - I know she was working on taking care of it when I was there, so I expect by the time you read this, it should be resolved. In fact, on the last night of my stay, I never heard it once.
Other than that one issue, I had a great time staying with Berenice. The best part about the stay was the location in the heart of Paris. She greeted me warmly and advised me on how to spend my few short days in Paris, which can be a very confusing city for a first-timer. Give her a call if you want to live like a local!