We had a great stay at Armando's place, clean, quite and confortable for a days of relax in Porto. The appartment is perfect for a couple, is 15 minutes away by foot from the Gaia's side of the Douro, and in 10 minutes you have the nearest metro station to the city center.
Joao (Armando's son) was very helpful and welcoming! Also there is a very good restaurant with great local cousine just below the appartment (A Tasquinha).
I would recommend this appartment to anyone who visits Porto.