We stayed in the apartment for a weekend, with four of us it was perfect. However I´m not sure about the claimed 8-person capacity, I think it would feel pretty cramped with that many people. Also, there's only 1 proper bathroom that's accessible to everyone.
It was clean and in good condition, and the host was friendly and accomodating. Bear in mind that there was a noisy street party nearby until 2am, so if you wanted an early night on a Saturday night then the noise might be a problem. Also there's no TV, but that didn't bother us as we weren't in Lisbon to sit on the sofa!