I was a solo long-term stay (3 months) and the apartment was perfect for me. I would have stayed longer if I could have. The apartment is fully stocked with kitchen supplies and prepared for everything you need for any length of stay. The kitchen is spacious and having the washer/dishwasher/oven/microwave was great.
The location is about a 20-30 minute walk to the city center and tourist destinations because it is in a residential area that I felt safe in. There is also a bus stop right outside and Uber is handy for longer distances. I preferred feeling like a local, so this location worked well for me. There are many schools surrounding the area so many families are around while school is in. There is a grocery store right around the corner (5 minutes walk) and another about a 10 minute walk a few more blocks away.
The main entrance is locked which is nice for safety. The apartment is split level on the top floor of the building. The patio is great right off of the bedroom which is upstairs. Sunsets are amazing. Catch every one you can while relaxing with a beverage and/or snack. Cheesy but I walked outside to the patio every morning and said "Good morning Portugal" looked around and started my day. The bed was comfortable and the bathroom a good size with a tub. There is space for storing clothes, etc which I brought 2 suitcases full of for the longer stay so that was great. That is harder to see in the pictures. I didn't feel cramped at all. The internet was very reliable and fast and this is often hard to find while traveling.
I was able to travel around Portugal by train (I didn't have a car) so the central location of Porto along the coast was perfect.
Hugo and Sarah were great. Any time I had a question or needed help there was great communication through WhatsApp (plus regular texting etc).
The best part for me as a long-term stay was that it felt like home while knowing Hugo and Sarah were there for me. I am glad I made the right pick going through the arduous AirBnb search.