We had a very pleasant stay at Antonio‘s! The building is very bright, modern and has a lot to offer: the common area offers a nice, fully equipped kitchen and living room and also has a nice little garden. The private room is very comfortable, has a nice bathroom and gladly, we also had a room with a balcony! We really felt at home and loved our stay there! Also, Paola (the housekeeper) is very charming and Antonio himself very caring (he texted us a few times if everything was fine and whether we needed something). The building is in a quieter area of Porto, but within walking distance to the centre and also a nearby metro station (3 stations to the center). As mentioned by a few other comments, there sometimes was a unpleasant smell coming from the bathroom - but for us, it was no problem and we think it also was due to the rain in porto. All in all, BIG recommendation for this Airbnb - we really loved it!
Best regards from Austria :)