We wish every AirBnB accommodation and host were as wonderful as this one! We travel quite a bit, using AirBnB's almost exclusively. This is perhaps the best one we've stayed in.
We have three basic criteria when we select an AirBnB: there must be a full, well-stocked kitchen (when you're on the road as much as we are, it's important to be able to comfortably cook some meals "at home"); it must have a washer (we travel light, so there's always a need to wash clothes), and it must have decent wi-fi. Sofia's place exceeded the mark on all counts plus nearly every other one you can think of. The apartment was larger than we expected and very clean. The location was superb. And Sofia always responded within minutes.
Note: If you use a face cloth, keep in mind most European homes do not have them, so you may want to put one in a zip lock bag and tuck it in your luggage.
If you are going back and forth between a couple AirBnB options in Porto, stop stressing and pick this one. You will be happy you did.