Really lovely small apartment, ideally located in the centre. the street is reasonably quiet and you are only a short walk from everything. Apartment is well appointed with everything you need although we didn't use the kitchen. We were met by Bernardo who was really helpful and friendly. We caught the metro from the airport to the city centre then its a 5 minute walk to the door. We loved Porto and its easily walkable (with hills of course).
The only two things we would say is there is a staircase climb up 4 floors to get to the apartment so no good if you have mobility issues, also and most importantly the church bell near to apartment rings every 15 minutes 24 hours a day so if you a light sleeper this could be an issue, if you sleep like a log then you might be ok, we would have loved to have slept with the window doors open but we couldn't because of the bells. If you are used to noise at night you may not find this a problem.
Everything is great about this apartment other than this.