I usually book directly with the hotel. I do use Booking.com, but mostly for apartments. I prefer booking directly with each hotel just because there's someone there, and it feels safer.
I really like staying in the Latin Quarter in Saint-Germain. I was there in early April of this year and loved it there I recently stayed at the Hotel Left Bank on Rue de l'Ancienne Comédie. I loved the location, and the hotel was very nice with a vintage vibe to it. There is a small lift and the hotel has A/C (although you shouldn't need it in November). :-) Our room was a triple, as I was traveling with two grandchildren, very clean, with two single beds placed side by side, and another single in a more secluded area of the room. This was nice as it gave my grandson a bit of privacy. The room was spacious and very clean.
The breakfast was an additional cost, but when I booked the hotel, they were offering it for €5 pp, so we got breakfast both mornings, and it was quite good. There were not only breads and pastries, but creamy scrambled eggs, crisp sausage links, fruit, cereal, yogurt, and tomatoes and cucumbers.
The location was outstanding. It was a block from the Odean Metro stop, about a 5-10 minute walk to Notre Dame, and it was so convenient to sights, cafes, boulangeries, pastry shops and much more. We only had to walk out the front door to find food and drink options everywhere. Plus Luxembourg Gardens was very close and we loved walking through there with all of its beauty. Our cost was around €320 per night for a triple room. If you book a double, the cost would be less.