Rita's place is a great option for Sintra. The space is amazingly stylish, clean, and comfortable. Rita is also so kind and generous and responsive. She communicated so well with me before our visit, and she was wonderful to meet. Her place is about a 4-5 Euro Uber ride from the train station but is also walking distance. She is also about a 4 Euro ride to Pena Palace (also walking distance but very uphill), easier and cheaper than walking back to town to take the bus. She is a few steps from a tourist office where you could get your tickets to Pena Palace and other sites (it unfortunately opens at the same time as the palace but if you could get them the day before it would save you considerable time). Her place is walking distance from the historic center also. I don't think you can beat this option in Sintra.