I can't say enough good things about this place and the host, Rita. I'm a solo traveler, and Rita and her mother both went out of their way on many occasions to make me feel welcome and comfortable. Rita even offered me food on my first night when I arrived late and was too tired to go into town.
The space is really lovely and had everything I needed for my stay in Sintra. It's well-located, far enough away from the busy touristy area so it's quiet and peaceful. Plus, one of the tourist buses (435) can drop you off right across the street.
One tip: Bring a light (a flashing bike light would be ideal) so cars can see you while you're walking on the curvy, narrow streets in the evening. Some parts of Sintra don't have sidewalks.
I will definitely stay here when I return to Sintra!