Cidália was very hospitable, she gave a lot of helpful tips about the places nearby and Lisbon in general. Cidália and Vitor were very kind to give us an extra set of keys even though we didn't ask for it beforehand.
The apartment looks very nice and is very well equipped. The furniture is spectacular!
A couple downsides:
2 of the 3 bedrooms don't have any windows.
It gets quite cold inside in the winter, and overall it's not a problem since there are enough electrical heaters inside to compensate for that, but unfortunately there is no heating at all in the bathroom.
We enjoyed the stay and certainly recommend Santos family's place, staying there felt very authentic.