Legality of cameras in vacation/holiday home?

I'm currently staying in a property in Portugal (Almancil) that has several Verisure cameras inside and outside of the house. I have seen the panel light up red on a few random occasions which led to me researching what this security system is. Apparently, the owner can watch us at anytime at his convenience on a mobile device/app. The cameras are in the main living area/room, a stairwell and the basement (cinema room). Both the owner and I are from the UK and I know this is illegal in the UK in private rentals.

Does anyone know the legality of this situation in Portugal? Is this allowed by the owner?

EDIT: Here is the link https://www.holidaylettings.co.uk/rentals/almancil/209560