Whilst the apartment is lovely and in a great location by the river, our stay was spoilt by the building work downstairs next door. So if you are booked in over the next 2 months I would reconsider. Work started 8am to 6pm every day including the weekends and made the apartment far from peaceful. I do understand that the owners cant do anything about that, but they could have let us know for us to choose then if we still wanted to stay. They failed to let us know so I'm posting this so future guests know as i doubt they will let anyone know in advance. When we questioned why they didnt inform us, they said they didnt know which doesnt seem plausible, given they got the room ready and greeted us to check in to the sound of a pneumatic drill !
The apartment also could have been better equipped. we stayed first in lisbon and there we were greeted with a few nice touches of milk and bread, yoghurts, fruits and carafe of port etc.
There are plenty of lovely places to stay so I'd consider others.
Other recommendations whilst im porto: porto free walking tour (take porto) which was great, ramos pinto cellars, and dinner at the o comercial.