We recently stayed for three nights for a long weekend to explore Lisbon.
The apartment is in a fantastic location within walking distance of all the main areas of Lisbon. We didn't take public transport to travel around the city once - although be warned it is very hilly!
The pre-communication we received from the hosts was great. We amended our check-in time as our flight landed early and it was no problem for them. Rita, who showed us around the apartment, was really welcoming and friendly. She recommended a restaurant around the corner for us to grab some dinner, which was delicious! She was also on hand (via WhatsApp) for any questions we had during our stay. We weren't flying out until the evening and we were able to leave our bags in the apartment and pop back to get them later, which was super helpful!
The apartment was clean and had everything we needed in terms of towels, linen, kitchen utensils etc. It is at the top of three flights of quite steep stairs, so do bare this in mind. The building itself is also quite old so you can hear the other flats if people are moving around or in the stairwell, so my only recommendation would be to bring ear plugs if you're a light sleeper.
In terms of activities in Lisbon, I would recommend the Sandeman's free walking tour, visiting the castle, a day trip to Sintra and By The Wine for food & drink!
Overall we really enjoyed our stay and would definitely recommend this place to people looking for a base to explore Lisbon!