Agree with 1. Ban AirBnB. (this is already in play as I understand it)

Silly tax incentives like Non-Habitual Residency have to go (done).

2. Actually already exists in the suburbs, but maybe now needs a bit of a make over. Of course the children of well-heeled Portuguese wouldn't stoop to live in such places while studying at University, but hey that's the world we live in!

3. The Golden Visa scheme is a nonsense (I think this is also being scrapped), but perhaps property taxes for places that are not the primary home might help with this.