I highly recommend Nina and Luis' place. Nina was wonderful about communication, and recommendations when we asked. The apartment is spacious, comfortable, and sunny, with everything we needed on vacation. The area is wonderfully walkable around historic Alfama, or for taking the tram or a bus around the city. There is a tiny convenience store right downstairs with all the basics--eggs, milk, bread, coffee, etc. Larger supermarkets are just over a kilometer away--accessible by foot or a short ride with public transportation. There are several coffee shops, bars, and restaurants within minutes of the apartment.
We decided to take an Uber from and to the airport and I recommend that to others. That way you can prepay and don't need to worry about being overcharged or having to pay with cash.
I am so glad that we decided to rent Nina and Luis' place and definitely recommend it to anyone looking for a spacious "vacation home."