I can't say enough good things about Anna and Christophe's lovely home! Not only was the space itself beautiful, satisfyingly unique, and absolutely perfectly situated within the city for my needs, Anna and Christophe themselves were incredibly accommodating when I had to make last minute changes to my check in date and time, due to an urgent matter that came up in my own life.
You have to climb a few flight of stairs, but anywhere worth staying in Paris (i.e. with a view!) has stairs to climb. Every little bit inside was exactly what I'd wanted, and as someone who gets quite cold easily, the heating units as well as the divine down duvet did their job in keeping me warm and cozy. Coming home to this place after a whole day of extended walking in Paris, dodging the rain, was an an measurable comfort and relief. One of my favorite things to do was to lay in the (unfairly) comfortable bed and listen to the rain patter on the skylight windows above, perhaps even catch the church bells ringing across the rooftops on a Sunday.
I am 5'3", or 160 cm, and I was perfectly comfortable navigating the apartment and the loft. It should be noted that my friend, who is 6'4", or 193 cm, had to stoop a bit to navigate the bathroom in the loft, and struggled to use the bath as nimbly as I could, due to the sloping ceiling, but these are details that should not dissuade you from staying here. You get a feeling that you are getting a uniquely authentic Parisian experience (not an Italian walk-in shower in some hotel), and that's worth a bath that requires a bit of dexterity!
I would absolutely come stay here again, the metro being so close and with so many good restaurants nearby, I have many good memories I will treasure. I can say that the night life on the street can be a little intimidating to encounter at first, as someone who doesn't frequent bars and clubs myself, but I never felt unsafe amidst the crowds, even as a woman walking down the street alone. Especially when all I had to do was go up a few set of stairs to escape it all, sit above the city again.
Stay here. Don't mind the cost. It is an experience in simplicity and history you won't soon forget.