Nomad Dreams so accurately describes this property. It is pristine, well decorated and has everything one would need for a short stay (or even longer) in Cascais. It has a lovely little balcony where I would often enjoy my cup of coffee and work, because the WiFi is great there as well.
It is tucked away on a side street within the bustling center of everything in Cascais, so it is easy to walk out your front door to the beach, grab dinner at Hifen, Cafe Clandestina on the yellow street (two of my favorites), or pick up that toothbrush at the market you forgot at home. That said, if you are looking for serenity and quiet you might want to request her other 1 bedroom apartment in the same building #3 which has newer windows and black out shades and a bit more quiet.
The owner Veronica is THE BEST AirBnB host that I have ever had. She is professional, helpful, and very attentive to everything you need during your stay.