The government has been told it could help another 4,000 families a year to get a foot on the property ladder.
More people could be helped to buy a home, the NAO says
A report from the National Audit Office (NAO) said the government needs to improve the efficiency of its shared ownership home buying schemes.
Only 11,000 households were helped by the Homebuy schemes in 2004-05 even though 60,000 applied.
Homebuy aims to help council tenants, housing association tenants and key workers buy part of their own homes.
The NAO says millions of pounds could be saved each year if the Homebuy schemes were managed more tightly.
Judith Watson, an intensive care nurse in London, was one person who used them last year.
"I bought 50% of my property and pay rent on the other 50%.
"I would never be able to get on the property market in London close to my work if I hadn't done the shared ownership scheme," she said.
"I no longer have to live in the nurses home which was one room."
In the last decade house prices have risen so much faster than people's incomes that in many parts of the country it is now impossible for anyone on an average wage to buy an average priced property without extra financial help.
The Homebuy policy currently encompasses three different schemes.
Broadly, they help selected applicants buy up to 75% of the value of a property, with a registered social landlord, property developer or mortgage lender owning the remaining stake to whom they pay rent.
Since Homebuy started in 1999, 40,000 people have been helped to buy part of their own property with the government targeting another 100,000 for help by 2010.
Julie Ralfes, a 30-year-old civil servant from Caterham in Surrey, found her income being rapidly outstripped by house prices.
She bought a two-bedroom apartment three years ago and was helped by a scheme run by her local council, aimed at local people rather than key workers.
She says it was a relief to be offered the opportunity.
"It was very easy. I got a phone call from the local district council when I got to the top of their list. It was a brand new development and the housing association contacted the council. I went and viewed the property and then it was a normal procedure for buying a house."
The NAO says more people could be helped if the schemes saved money by:
- targeting social tenants
- ensuring repayment of loans by key workers who left their jobs
- encouraging buyers to take on a larger stake in the property
The Department for Communities and Local Government said the report was very helpful.
"We want to go much further and have set up a shared-equity task force to look at expanding shared ownership," said a spokesman.