First home buyer Casey Westcombe said the two-year delay for work to begin on his three-bedroom house was "paralysing".

The 32-year-old said he didn't think he would ever afford to buy a house in Canberra, so he jumped at the chance to buy in the ACT government's affordable home purchase scheme.

The scheme, administered by the Suburban Land Agency, offers homes for sale at an affordable price to low- and moderate-income households.

To be eligible, applicants must be first-time buyers and must meet household income limits, for example $100,000 for households with up to two children.

Mr Westcombe received an email from the ACT government in December 2021 about 13 affordable homes for sale in Whitlam, the newest suburb in Molonglo Valley.

It advertised three-bedroom homes on blocks of up to 244 square metres priced at about $441,000.

The email stated the properties "will commence construction late 2022" for an expected completion date of 2023.

Mr Westcombe accepted the completion date was subject to change, but believed construction was confirmed to commence as stated.

"I was like, great, I can trust the government on that," he said.

Once he was approved for the scheme, Mr Westcombe said things moved quickly. In April 2022, he signed a contract with the government's chosen builder, ALN Constructions.

Since then, he has paid about $33,000 to the builder and is paying mortgage repayments on the block of land. He is also paying rates on the property and sewage supply fees.

Mr Westcombe estimated he had paid about $90,000 for the property so far.

Meanwhile, he is still paying for rental accommodation while he waits to move into his home.

A Suburban Land Agency spokesperson said construction commencement dates referred to in the scheme's communications "were advised by the builders".

"SLA continues to follow up with the builders for updates and relays any information it receives from the builders to the buyers," they said.

Under the building contract, ALN Constructions has 30 days to begin construction after receiving building approvals, which it says it has not yet received, and then has 270 business days for the construction period.

A spokesperson for ALN Constructions said factors outside the company's control, including recent building code and regulation changes, contributed to the delay in receiving building approval and beginning construction.

The group intends to start construction at the end of April.

For two years, Mr Westcombe has been in contact with the ACT government about his build, but felt little had been done to move construction along or provide accurate timeframes.

When he asked to see the project delivery deed, a contract between the Suburban Land Agency and the builder, he was told to lodge a freedom of information request.

He did so and found the deed states the builder has four years to complete construction of the homes from the buyer's purchase date.

The ACT government recently agreed to meet with Mr Westcombe in March to discuss his situation.

The wait for construction to begin has prevented Mr Westcombe from making other financial decisions.

"If you're reasonably weighing up whether you can afford to change a job or have a family or make any sort of life decisions, there's just this very extreme kind of paralysis," he said.

He has sought two, year-long extensions on his construction finance loan and continues to rent a home.

"In the meantime, I'm stuck in the rental market," he said.

"I think it ceases to be an affordable anything if you get stuck [renting] for years on end."

The Suburban Land Agency spokesperson said the scheme is designed to connect eligible buyers and builders and the individual projects are not managed by the ACT government.

"Once a buyer is matched with a developer or builder, the process from exchange through to settlement is the same as an open market property sale," they said.

"Construction contracts are between the buyer and the builder, and the construction program is administered under that contract.

"The ACT government is not a party to these building contracts. SLA encouraged all buyers to seek financial and legal advice before entering into contracts with the builders."

Mr Westcombe said the ACT government needs to take some accountability for the delays.

"I think there's a duty of care, particularly when you're advertising [homes] to people that have less agency, in that they are in a position to be eligible for an affordable housing scheme," he said.