Zack Polanski, leader of the Green Party, is to call for a three-year cap on private rent rises, as the BBC reported. The intervention lands at a moment when the private rented sector is already under intense scrutiny from policymakers, and it adds a fresh, more radical voice to a debate that has so far been dominated by the government's Renters' Rights reforms. For a market participant base that includes buy-to-let landlords, institutional build-to-rent investors and millions of tenants, the prospect of statutory rent caps — even floated by a party without a parliamentary majority — is the kind of policy signal that shapes investment decisions long before any legislation reaches the statute book.