I stayed here with my spouse for the last week of August.
This really is a lovely hotel run by a kind, gentle, and helpful staff.
The decor is adorable, it's easy to get to the sights from here by metro or bus, and the neighborhood itself has loads of excellent restaurants and cafes nearby.
The bed was verrrrrry comfortable. Even more so than our bed at home, and it was easy to regulate the temperature of the room. Since I like it colder than my wife, she wanted the extra blanket. Our first extra blanket was a little scratchy, so it was swapped out promptly and cheerfully by the nice lady who cleaned our room every day for one that was soft.
Our room was spotlessly clean and had a great window that opened easily with a view of the street in front.
The only small caveat I had was that the room was quite small. It was not easy to navigate around the bed and there wasn't much room for our stuff. That being said, space for us was not a priority, and we did reserve one of the smaller rooms. I seem to recall from the website that they have larger rooms available as well.
The bill at the end was exactly what I expected to pay. There were no hidden charges tacked on.
Breakfast was good and plentiful. Most cafes in the area will charge between 7 - 10 euros for a "Petit Dejeuner Formule" - a prix-fix breakfast consisting of a croissant, a piece of buttered, toasted baguette, jam and a hot beverage, sometimes with a glass of orange juice, sometimes not. With HdlP's breakfast, 9 euros gets you all the above plus yogurt, ham, cheese, a selection of cereals, and probably one or two other things I didn't see. It's also buffet-style, so you can eat as much as you like.
I would not hesitate to recommend this place to anyone looking for a nice, adorable, authentically Parisan place to stay in a great location at a good price.