Economist Vera Gouveia Barros argues that the most effective element of the Construir Portugal programme is tax relief on rentals, citing an ‘almost mechanical effect’ from a proposed 10% autonomous IRS rate for rents up to €2,300. She suggests this tax cut will directly influence rent levels and landlord behaviour, with likely quick transmission into the market. However, the package omits a dedicated room‑rental option — a gap that could limit lower‑cost housing supply and options for students, workers and expats. Barros’ analysis implies policymakers should pair fiscal incentives with targeted measures for small‑unit and shared accommodation and monitor market adjustments to avoid unintended rent inflation or supply imbalances.