The house is big and clean, it was great staying at his place. Paulo and his dad was really kind and responsive. His dad does not speak English, and speaks a bit of Spanish, but we worked it out all well with Spanish and gestures.
The location can be a bit far from the touristic area, but it is on the hill, so you get to tour around the old town part as you walk towards the river. My family and I liked it better to tour that way instead of touring all around the river and then walking up the hill to the old town.
We loved our stay at his place, and we had a great experience in Porto!