Instead of putting in place reasonable rent rules, the Government could increase the subsidies it pays to people on low incomes to help cover housing costs. The Government already pays out nearly $2 billion a year for the Accommodation Supplement, to more than 350,000 households (some people use this to pay mortgages, but most use it to pay rent).
Currently, the most a single person can get is $165 a week, families with children can only get $305 a week, and only lower-income earners qualify. The Government could increase the amount of subsidy people are eligible for, and it could also make more people eligible for this subsidy. This would not make rents more reasonable, but it would help more households be able to afford to pay rent. It is possible that in response to the higher subsidies, landlords would raise rents, knowing their tenants can pay more.