Maria Helena is a great host! Before arrival, she was in constant touch with advice about the best way to get there from the airport or the train station. She waited for us to check in around 10 p.m. and, as it was our first time in Lisbon, she gave us some friendly advice about not accepting "help" from people on the streets who might try to scam us. The next morning, she allowed us to keep our luggage till we came back to pick it up in the afternoon (as it was a noon checkout and we wanted to roam around in the morning without being encumbered by our luggage). She also gave us some more friendly advice about taking the metro to the airport.
The apartment is very close to the metro, the room was super clean and very homely, and the bathroom (with a huge bathtub!) was huge and very clean too. The room is big enough for two people with furniture for storage as well. Ventilation is from the window that opens out onto the street.
All in all, a nice, homely place to stay for a great price! Will definitely consider returning.