I stayed at Mathieu's place for 4 months and can truly recommend this cozy room. I always felt comfortable, actually like being home. Mathieu is a great host: He is very helpful, funny, an excellent cook and such a lovely person.
You can reach the metro station Guy Moquet (no. 13) within a 5 minutes walk and metro station Jules Joffrin (no. 12) within 10 minutes. There are several supermarkets, delicious bakeries, bars and restaurants in this neighborhood, so everything you need. Additionally, the Sacre Coeur and Montmartre are only 20 minutes by walking which are my favourite places in Paris.
I had an awesome time - thank you so much Mathieu!