We stayed at Lina's place for a week in August and had a great time. The apartment was the perfect size for us (2 adults and a one year old, we even managed to squeeze my mum in for a few nights for babysitting help!).
It was very clean and Lina had bought us a few essentials which was really thoughtful. The apartment is a two minute walk from the beach and some lovely little restaurants (the tapas place is amazing). The only negative for us were the stairs inside the apartment and leading up to the block - we were aware of these but hadn't considered how tiring this would be with a buggy and heavy baby in the heat!
Lina was a great host and we loved Estoril and would recommend this apartment to anyone.