The house is great. Kitchen is a good size and there are plenty of bedrooms / bathrooms (however the lounge would be cramped if you had a full house). We rented the house as a couple, plenty of space, and it's nice coming home to a garden.
Carcavelos is a great location for visiting Lisbon: 30 mins drive into town, 20 mins to Cascais, 20 mins to Sintra, Carcavelos beach within walking distance, and there are several very good neighbourhood restaurants nearby if you don't fancy heading into town (Shangrilla Nepalese, Aashiana Indian, Taverna D' Pereira for grilled meat & fish, Taberna Oporto for a small home-cooked menu, and a couple of good cafes on the main road).
The house is ideal for pets. We bought our 3 dogs up from Algarve, the garden is completely fenced so no worries there.
Tip: If you are not an experience city driver, Lisbon can get a bit tight / congested but we installed the Via Verde 'Estacionar' app and always found convenient parking (billed to our Via Verde).