Tomas was extremely helpful and professional throughout the process. He emailed instructions with the best way to get to the apartment well in advance, and there was a detailed guide book waiting for us when we arrived that included restaurants, attractions, and maps.
The apartment itself was very clean and fairly well-appointed. A wine opener would have been nice to have, but we successfully cooked fajitas for dinner without any issues, and the location is very convenient to all the sites in the old city.
The apartment can be noisy in the evenings depending on other residents/guests. Also, there is no A/C (which is not necessary in Porto), but the area can be loud overnight with the windows open.