Mr Coe sought again on Thursday to explain how a Liberal government would fund its election policies, including its four-year residential rates freeze and cuts to car registration fees.

The Liberals also promised in 2018 that they would abolish payroll tax - which is worth more than $500 million a year to the ACT budget - if they won government.

While details of the plan remain almost non-existent, Mr Coe has made clear that the Liberals believe they can cover the revenue hole, and continue to fund public services, by enticing more people to live and work in Canberra.

Chief Minister and Labor leader Andrew Barr has panned the "Alistair Coe economics", saying a government would simply have to spend more money on services and infrastructure to meet the increased demand.

Mr Coe has for weeks sidestepped questions on how the Liberals would fund their commitments, which would leave the coronavirus-struck ACT budget hundreds of millions of dollars worse off.

He has maintained that he wants to make Canberra's housing and cost of living more affordable, which he believes is the key to stopping families from leaving the ACT to live in border communities such as Queanbeyan, Googong and Jerrabomberra.

On Thursday, he provided some further explanation on how retaining families in Canberra would help to grow the size of the ACT economy, and help to fund services.

"For every house that is built on the other side of the border, we of course lose that land sale but we also lose the rates revenue and the federal disbursement (GST grants) that comes with population growth," he said.

"The Canberra Liberals think it is right that people who grew up in Canberra should be able to live in Canberra.

"By harnessing more of growth here in Canberra and here in the ACT, not only would you get that benefit from the initial land sale, but importantly you'll get the revenue that comes from having more rate and taxpayers in Canberra."

When asked if the Liberals had done modelling on how much the population would need to increase by to cover the revenue hole, Mr Coe said it was still early in the campaign and further announcements would be made in the coming weeks.

The Labor leader said Mr Coe's plan to cover lost revenue through population growth would not work, as extra public spending would be required to meet extra demand for services.

"I think the point to recognise here is that a greater population means greater demand on service provision," Mr Barr said.

"If it was just a simple case of having the biggest population possible and you don't have to provide any services to them then Alistair Coe economics might work."

He estimated that to make up for the revenue lost through the Liberals' commitments Canberra's population would have to grow by 50 per cent.

Mr Barr said while Canberra-based workers who chose to live in regional NSW might be able to purchase cheaper land across the border, they would have to spend more on commuting.

He also pushed back against Mr Coe's claims about a lack of options for detached housing in the ACT, saying there was affordable land on offer in Gungahlin, Molongolo and Ginninderry.