Estefania's place is an excellent place to stay at Porto if you want a bit of space and attentive hospitality. Well-equipped kitchen, nice little parlour, and two bedrooms with comfortable beds. The shower was good and high for us tall people, though the hot water didn't last long, I think the boiler must be quite small. There's a little terrace outside, though I didn't use it much in February.
The location is a few minutes walk from the Jardim do Morro metro stop (very handy for the airport, with one change in Trindade) and a downhill walk to the wine caves. (But that means an uphill walk to return :) You can walk into Porto old town in 10 to 15 minutes, across the famous bridge. But there are also small shops and restaurants nearby if you want to avoid the tourist areas on the riverfront.
And I can assure you that Estefania and Adelino will take care of you. I arrived later than expected but that was no problem for them, fortunately. The hosts will show you some local places to visit, and give some good tips as only a local can. But they will help when things go wrong too. One morning, the Wifi failed, and this was bad because I had to work. The hosts immediately looked into it. Although the problem was a temporary outage on the outside lines (so nothing they could fix), it was clear that they were going to take care of it as best they possibly could. This was very reassuring. So nomad workers rest assured (the internet was not the fastest, but good enough).
The only slight downside was that the windows in the bedrooms are not very soundproof, and you can hear cars pass and dogs bark. It's on a tiny lane so there's never any big traffic, but very light sleepers might want to keep it in mind.
I would happily come back and stay again, and I probably will because there's more port wine to try.