The rue de Mouffetard is lovely, friendly people, good restaurants would esp recommend 'Ô Jia' , fruit and vegetable stalls, wine shops...everything you need in one place. The Jardin des Plants is 5 minutes walk and an amazing visit. All in all the location is great.
I would agree with previous reviews that the cleanliness of the apartement is not ideal and if you are a light sleeper the neighbours are noisy during the night. The fire is a very welcome part of the apartment, if you are interested in using it please take into account that you need to purchase wood and firelighters etc...and there is a general/old fashioned style ironmongers store down the road which sells everything you need.
Ours was a last minute trip, the price was good and although we never met Roy he was very helpful.