My wife and I spent a night at Sofia's place when we were in Porto for a wedding, and we could not have had a better experience during our stay. The apartment is located in a great safe area, and it is charming and clean. Sofia made us fell welcomed by meeting us when we arrived and she went out of her way to make sure that we had the best experience possible. The communication was excellent before and during our stay! We stayed at 4 other places in different cities during our trip, and this was certainly our favorite one.
If you are looking for an excellent host, great location, and an outstanding place, I would certainly recommend staying with Sofia.