Daniela thanks for a wonderful time in Porto and your place is really 5 star! Thank you for being so flexible and accommodating with our arrival and departure times. You are right, it is a small city! (We stayed Sunday to Sunday end March and the weather was fair and lovely.) It was easy to walk!
Also, we can recommend the RED “hop on hop off” - the 2 day ticked is a great deal and full route gives good glimpse of the whole city - beach, old, new, and 2 bridges! Over 2 days at a fraction more than 1-day ticket. (Did not do yellow or blue bus)