João's apartment was really good to stay in Lisbon for a few days (my wife and I stayed there for 5 nights). Close to convenient stores and public transports (even if we didn't use them). But also, if you don't mind walking, close enough to "must see" places in Lisbon.
Communication with João went great, he sent really good instructions for check-in and was helpful during our stay.
Only negative points: there are no elevator in the building and the apartment is on the 3rd floor (but that's really common in Lisbon), and neighbours can be a bit noisy, but that's only during the day (no issues at all at night or in the morning).
I strongly recommend!