Mario is very nice and friendly. He gave us useful advices for visiting Porto. His flat is clean and clear. We slept in a room with a big bed, very comfortable. His wife gave us another quilt in case that we got cold. It's convenient to go to his house from the metro station. The location of this house is very good, we went to the Aliados on foot, we also walked to the riverside. We've spent two sweet night in Porto. :)