This place is absolutely, and utterly, amazing. We have stayed in at least six Airbnb apartments in Paris in the last five years, and Louis's apartment has been the best by a long margin.
It has an extremely cozy, bright, lofty feeling, with beams in the ceiling, very tasteful decor, and a view that seriously takes your breath away every morning. An apartment in Montmartre that has such a sweeping view of Parisian rooftops and such a full view of the Eiffel tower is RARE. Especially with such a good amount of space that is super functional, with a second bed in the mezzanine.
Louis was a fantastic host, responding to any questions immediately. His place is also very well stocked with everything from a washer and dryer (also rare), bath tub, awesome kitchen utensils etc, hair dryer and so on.
This apartment has a very authentic lived-in feeling, all in the center of Montmartre and a 5-minute walk from the Pigalle metro station. And it was so quiet. Basically after 24 hours we wanted to buy the place. Sadly it's not for sale :)