Stay in Guillaume apartment was completely terrific and superb. The place is very clean and very neat yet really stylish. I love the way Guillaume put the style of the apartment, the white ambience, the smell of the aroma therapy he got (actually I don't really like aroma therapy but this was an exceptional when I was on his apartment. I loved it) made me really calm and I feel like I do not wanna go out but since I realized I was in Paris I have to walk out.
About the view, you COULD NOT get any better view of Paris from the top of the hill in Montmartre like his place. You could see Eiffel tower, Les Invalides, etc, from the window of the living room while you enjoy your meal or wine or cheese.
About the location, it is very very close to the Sacre Cœur. When I said very very close it means very very very close. So you just walk upstairs and you could see Place du Terte and voila the Sacre Cœur.
About Guillaume, he is kind of warm welcoming person. He was there when I arrived and greeted me by himself. The communication was fast responsive so I didn't find any difficulties to contact him. Like I said, I just loved how he put the style of his apartment. He has a good high of taste.
Well, this place is really really recommended. I would definetely be in this place again when I visit Paris in the next trip. Definetely 5 stars