Marine's place is really cozy and comfortable and definitely worth staying in while you are in Paris. It is in a charming residential neighbourhood surrounded by several restaurants, little grocery stores, bakeries, and cute shops. Several metro stops and bus routes are a short walk from her building so getting around Paris is quite easy. Also as a solo traveler I found it to be safe even late in the evening.
Marine is also quite sweet and responds quickly to any queries or problems. I would definitely return to this apartment again!