We are a 7 people group and stayed at Nuno's house for São João, Porto's biggest party. The house would've been a bit small if we were staying for more time, but as we were only sleeping (not a lot of hours) for two days, it was perfect! It was clean, and had all the needed commodities.
The only thing to be mindful of is that the rooms are both upstairs, and the stairs are a bit tricky if you have mobility issues (or if you're afraid of heights!) but there is nothing wrong with a bit of a challenge ahah :)
Nuno was very thoughtful and available, and we're sure to come back when we return to Porto.