Antonia and Maria's place was perfect for our 5 day stay in Lisbon. We were a few minutes walk from one of the main squares and appreciated the quieter streets to sleep at night while still being close to all that was happening. The apartment is well equipped and seems like Antonia and Maria have thought about everything - we loved it! The bed was super comfortable and the living area was spacious and full of light from the three big windows. They kept out the noise and street lights for a good night's sleep! The apartment has great little restaurants along the street, our favourites being Sr. Lisboa and Taberna Anti-Dantas with the owner Felipe, also Susannah and Mario - awesome people! Our other favourite place we ate at twice and would highly recommend is Taberna da Rua Das Flores. They don't take reservations so get there early enough to put your name on the wait list and be willing to fill in some time until you get seated. The food is definitely worth the wait! We had cocktails at Le Consulat in the little square up the hill while we waited.
Our recommendation for a first time visit to Lisbon is to take one of the free walking tours around the city to learn the history and significance of everything you're seeing (donation at the end), and an e-bike tour (we got a good deal through Trip Advisor) and see Alfama that way (helps with the hills). We then returned the next day on foot to Alfama to see the highlights and enjoy the food and wine.
We took the train to Belem and spent an enjoyable day there - yes, go to Pasteis de Belem for a delicious treat (pass the take away line that extends down the street and find a table inside. You may wait a little bit but not overly long. The Maritime Museum that's housed in Jeronimos Monastery is well worth the visit also.
All in all, a wonderful time and we would not waste any time looking for other accommodation but would return to Antonio and Maria's beautiful apartment!