The apartment is just as described and depicted on Airbnb. The location is very central, about a two minute walk from Jardim do Principe Real and only about eight minutes walk from Miradouro São Pedro de Alcantara and Elevador da Gloria. There are plenty of restaurants and bars nearby in Bairro Alto as well and there is a little binder in the apartment with recommendations by João for places to eat, too.
I enjoyed exploring Lisbon from this little gem of a place very much! It is easy to reach Baixa, Mouraria and Alfama by foot, but public transport is also available (nearest bus stop is Principe Real - don‘t get off with your luggage at Avenida da Liberdade because that way you will have to haul your bags uphill to the apartment). I mostly walked down to the lower parts of the city and caught bus 758, tram 24E or the Elevador da Gloria to get back up.
João is a very nice host who communicated well before, during and after the stay. I arrived a little early and I was able to drop-off my bags at the apartment even before check-in so that I could take a little walk while waiting for check-in. João also let me check-in early as soon as he had the aprtment ready which was great! I ended up forgetting something in the apartment and João immediately agreed to send it to me and actually mailed it the same day!
I highly recommend staying at João‘s apartment!