I stayed at Sabrina's apartment for 1 week as a solo traveler and overall was satisfied with my stay. The directions to check in were easy to follow and I felt welcome immediately after meeting Sabrina. The walls are very thin so noise easily moves through rooms, but I had no issues sleeping.
As for the location it's right in the middle of the Eiffel Tower and Luxembourg Gardens (about 1 mile to 1.5 mile walk). If you want to go anywhere in Paris it's very easy since there's 2 Metro stations within a few blocks. Also, I highly recommend visiting the Palace of Versailles, which is very convenient from Sabrina's apartment since you take the train from Gare Montparnasse (only a few blocks away).
Overall, Sabrina's place is a great value for experiencing Paris and I would recommend to fellow travelers.