We had a great time in Casa do Mestrinho while travelling with our 5 month old baby. Teresa and Pedro are incredibly friendly and helpful. It was great to have some welcome essentials like bread, milk, ham, some eggs from the chickens in the backyard and a incredibly tasty homemade marmalade and of course some fresh coffee waiting for you. The house is really nice and we enjoyed the beautiful and calm garden with a great view to Porto and the Douro.
Also the people around this place (e.g. in the little store across the street) are very friendly and this made it a great base for some Porto and Douro valley explorations. Be sure to come by car and drive to the church first (our gps tried to get us there from down at the river... streets are too narrow there).
Thanks Teresa and Pedro for letting us stay there - we'll come back.