I heartily recommend Cristina's apartment. You can't beat the breathtaking views of Porto from the intimate balcony. (Note: there are a lot of construction cranes - a sign that Porto is going through a development boom. ) I'm impressed how Cristina thought of every detail to make our stay so comfortable - from the small bottle of port to sightseeing and restaurant tips. She personally checked us in, which was a special touch.
If you go to Porto, you should try to stay at least three days to experience the city. There's a lot to see!