Rebecca Lewis and her husband were successful in a ballot to purchase a house and land package in Whitlam as part of the ACT government's Affordable Home Purchase Scheme in 2021.

The builder terminated contract negotiations six months later, forcing the couple to buy at a time when house prices had risen considerably.

Ms Lewis wants the ACT government to take responsibility for her family missing out on owning a three-bedroom home in the scheme.

The program, which offers home ownership to households on low-to-moderate incomes, has also faced criticism from buyers who have been waiting two years for construction to begin.

The ACT government says it is no longer offering house and land packages as part of the program.

The Lewis family were notified by the ACT government's Suburban Land Agency in mid-2021 they were successful in the housing ballot.

They were offered a house and land package in Whitlam at an affordable price of about $440,000, to be built by a construction company chosen by the agency.

The couple engaged a solicitor to help them negotiate the building contract from the agency's chosen builder, ALN Constructions.

Ms Lewis said there were "red flags" in the various versions of the contract the builder provided that the couple sought answers on. Among them, they wanted confirmation in the contract that it was a fixed price arrangement.

Their solicitor had also requested one of the construction progress payments be reduced to 10 per cent, as several lenders would not accept the 15 per cent payment outlined in the contract, Ms Lewis said.

When the builder did not agree to the changes, the couple said they "moved mountains" to ensure they could exchange, including finding a new lender who would meet the builder's requests.

In a later version of the contract, the couple also sought to remove a clause that prevented them from inspecting the construction site.

Through the contract negotiations, the Suburban Land Agency remained in contact with the Lewis family and extended the timeframe they had to exchange contracts.

Ms Lewis said they had paid their deposit and their solicitor was ready to exchange when the agency told the couple they had been terminated from negotiations on the home.

"ALN Constructions has advised us that due to the extended timeframe taken to exchange a building contract on Block 5 Section 3 in Whitlam, and an inability to agree on the terms of the contract, they will terminate contract negotiations with you," an email from the Suburban Land Agency stated.

"They will then request an alternative eligible buyer via the Affordable Home Purchase Scheme."

The couple maintains they met the deadline to exchange and believes their contract was terminated because they "asked too many questions".

"[Our solicitor] said to us 'they don't want to build for you' because we were just doing too much research," Ms Lewis said.

"We knew a lot of things. We were asking a lot of questions."

An ACT government spokesperson said successful ballot recipients become part of the scheme after they exchanged contracts with a builder.

Ballot recipients can be "removed from the offering" if they request to withdraw, are deemed ineligible or if they don't exchange within the designated timeframe.

Ms Lewis said she was unhappy with how her situation was dealt with by the Suburban Land Agency.

"I'm still really angry," she said.

Recent news coverage about delays to the scheme had prompted her to contact the Suburban Land Agency again.

The couple asked the agency to sell them a block of land at the affordable rate from 2021. A Suburban Land Agency employee informed the couple it had "no mechanism" to offer a block of land at 2021 prices but said there was land available to purchase over the counter.

The Suburban Land Agency says it is not a party to the construction contracts in the scheme.

"Final contracts are agreed between the buyer and the builder, for which SLA is not a party. SLA encourages buyers to seek independent legal and financial advice to inform their decision," an ACT government spokesperson said.

Ms Lewis said she wants the government to take more of a responsibility for the scheme and compensate the couple for their financial loss.

"They were the ones who set up this program. They should be dealing with this. We should not have no home in this program," she said.

ALN Constructions were contacted for comment but had not responded before publication.