We were amazed by Bela and Carlos' place. The location was nice, an hour walk from the city center (also frequent buses and very affordable shared-economy car services). There is a grocery store just a few minutes from the place, the MAAT museum is 15 minutes walking distance. Bela and Carlos were very hospitable, living in a flat just opposite and helped with anything we needed.
The apartment itself was amazing. Very nicely decorated, very cozy, and really, really sparkling clean.
It felt like home :). Would definitely return here if ever came to Lisbon again.