Vitor has a flat in the apartment building where he rents out a room. It is very close to LIS airport and Lisboa-Oriente rail terminal, which is exactly what I needed at the end of my Portugal trip (one day trip to Porto and flight next day). It is about 10 minutes walking from either Olivais or Cabo Ruivo metro stations, 20 minutes walking from Oriente, and 5 minute driving from airport (taxi is about 5 euro).
The room is clean, has table and enough power outlets, clean bedding and towel were provided. There are 2 toilet rooms, and one bathroom (they are shared). There is enough parking on the street.
Vitor was helpful and always ready to answer questions. Checking out is easy, you can just leave the keys and shut the door.