We went with our nearly-four-year-old and my mother for a week's holiday in early May. We were *thrilled* that Pedro offered to pick us up at Lisbon airport, and my husband put the car seat in and out of his car for the trip. He's really knowledgeable about the area, has good spoken English and I think French, and lives locally. Communication re: wi-fi codes and leaving keys at the end was seamless. He was very helpful about booking us a taxi for the return, and explaining the carseat magilla (€40 plus tip, for what it's worth).
The flat is in a modern, terracotta-roofed building on a steep hill five minutes on foot from the middle of Cascais, which has WAY more to offer than I expected, although I hadn't done much research to my shame – loads of restaurants, little city beaches, gigantic harbour, historical sights and a magnificent modern art museum (Paula Rego). The trains in and out of Lisbon run regularly and are comfy and fast, 40 minutes.
There's a lovely open-plan living/dining room, a balcony with seating for four outside – sea views through the rooftops from both, baking sun outside for much of the day. The kitchen is well stocked with everything you need to cook properly, so do make the most of the Wed & Sat market, which is incredible. The master bed downstairs is nicely decorated and quiet, with plenty of room and a nice bathroom.
Upstairs is good accommodation for kids old enough to do the steep stairs carefully; there is a baby gate installed for smallies, which was much appreciated. We slept upstairs in the small double, but the ceilings are too low (in either bedroom or bathroom) to stand up in most of it (we're both 5 foot 8) – so decide for yourselves.
Pedro is a great host. It's good value, comfy and homey, and the location is great.