It is a clean, cozy, and recently renovated apartment in a safe and quiet place just on the ocean cliff. There is a large private terrace with chairs and tables in front of 4 similar apartments owned and managed by the same host. The host is professional, nice, and responsive. Eg, he agreed to put curtains on the glass front door and windows when we asked him to do so as we were not comfortable while our neighbors looked at us while they were passing by.
The minus of our stay at the apartment was that it is not that big. I think it is around 35 sq meters. It was not as convenient for us to work and rest for 10 days as we intended. So, we ended up leaving the place a few days earlier than expected. Also, it was foggy for most of the time while we were there at the beginning of October. I was told that there was not much sun on the Sintra ocean coast if compared to Cascais or Caparica. Having said that, I would think that it is a great stay for 1-2 days to explore the area around.