Joana’s place is very nice—comfortable, charming artwork, lovely private patio with outdoor furniture. There is a washer and dishwasher, which is very handy. It is in a peaceful spot a bit outside of Sintra. If you want to stay in Sintra, this is an excellent choice, but I want to say a word on Sintra itself:
It is crowded with tourists even on a Monday in October. We could not find parking anywhere near the train station, so we drove back to the apartment and walked the 20 minutes in to town to get the train. The train station was especially hectic, and a local man (a commuter) told me it is like that all months of the year. Also, though Sintra and Joana’s place are officially within a Natural Park area, note that this does not mean a national park or preserve. There are many buildings, houses, and busy roads.