We had a great stay in Estoril at Anna and Alfonso's place. The apartment is really lovely with lots of amenities and a great view! Alfonso was easy to communicate with during the stay and offered some great suggestions for restaurants in Estoril, Sintra, and Cascais. They had a welcome bottle of wine, cheese, and crackers waiting for us which we thought was an extra special touch. The location was great - about a 12min walk to the beach area and other restaurants and cafes.
Two tips: Give the door key a good push inwards when turning (it took us a bit to figure it out). Also - although we didn't see them, there are peacocks close by. They were quiet our first night but pretty chatty during the other two nights. I'd bring some earplugs just in case you experience the same. Otherwise, it was a beautiful, quiet spot to stay.