Really enjoyed Susana & Miguel's place. The location is amazing, we were right in one of Lisbon's old streets, very close to a stunning lookout and within walking distance of great restaurants, cafés and bars. Lots of public transport options are nearby as well.
The house is very comfy and, although small, the available space is very well used so it never actually feels small. The kitchen is well equipped and appliances work well.
The only negative is that it's an old building and thus one can hear the neighbors every once in a while. Still, this wasn't too serious as they're generally respectful of the time.
Definitely recommended.