Canberra's real estate agents have also cautiously welcomed the proposal, as all stakeholders await more detail, and where the Legislative Assembly will sit on the idea.

Greens MLA Caroline Le Couteur will put a motion to the Legislative Assembly calling for the idea, which could see landlords given a tax break in return for cutting their market rents by 25 per cent, to be debated by local politicians on Wednesday.

Community Housing Industry Association ACT regional director Andrew Hannan said the sector, which would play a key role managing the tenancies, had welcomed the proposal, given it has previously called for such an arrangement.

Mr Hannan, also executive director of CHC, Canberra's largest community housing provider, said it also aligned with plans for the government to help fund a new private philanthropic real estate firm.

He said the sector had long recognised such a proposal could help leverage other people’s balance sheets to grow supply to meet the demand for affordable rental properties in town.

“Community housing providers don’t necessarily have the financial means to materially grow their portfolios on their own, so this would enable growth by tapping into a third-party owned asset," he said.

“It has the potential to more rapidly close the supply-demand gap without necessarily needing to build new affordable rental housing."

Housing Minister Yvette Berry said the government was also preparing to announce a 'successful provider' for the bid for a not-for-profit real estate agency or community housing provider to manage affordable properties in coming weeks.

But it is unclear if that proposal, set to secure some of the government's $1 million affordable housing innovation fund, would extend to potential tax breaks for such landlords, as the Greens have proposed.

Mr Hannan said the minor parties' proposal could potentially make available more detached houses in inner to middle Canberra suburbs, with a higher land value, compared to apartments or homes in outer suburbs.

He said the community housing sector was waiting to see what policies the government would take up when it releases its new affordable housing strategy, though the Greens proposal could also give the wider community a chance to help address the problem directly.

But Unions ACT secretary Alex White claimed it was 'neoliberalist nonsense', that would give property investors yet more tax breaks that he believed the Labor-Greens government should not act on.

Despite landlords needing to contribute themselves to the cost, in foregone rent, Mr White said he believed it would only benefit landlords, and if investors wanted to contribute by reducing the rent, they did not need a government subsidy to do so.

The Real Estate Institute of the ACT's chief executive Michelle Tynan supported the idea in principle and was open to further discussions, the institute had not yet received any details from government about the proposal.

“For example it is unclear how many affordable properties would actually be provided to families on low incomes or whether it would just be a reshuffle of properties that are already on the lower end of the rental scale," she said.

Ms Tynan also said the agent's peak body wanted to know why properties would need to be managed by a community housing provider, rather than giving owners the option to choose who they wanted to do so.

Ms Berry also said potential incentives to encourage private landlords to rent their properties at affordable rates was still being considered, but the focus in the upcoming housing strategy would be on people on lower incomes.

"My priority is to make sure any public investment or subsidy would have a clear benefit for them," she said.

The Canberra Liberals did not respond to a request for comment.