Banks have begun to unveil mortgages which they will offer under the expanded Help to Buy scheme.
The government's initiative is designed to enable buyers who can afford only small deposits to buy a home.
RBS, NatWest and Halifax will start taking applications this week and Virgin Money will join from January.
There have been concerns the scheme could cause a housing price bubble but ministers said it would help people get a foot on the property ladder.
RBS and NatWest are offering a two-year, fixed-rate mortgage starting at 4.99%. Halifax will be taking applications in a few days.
GuaranteesThe scheme is getting under way as surveyors report their sales levels are at their highest for nearly four years.
The Royal Institution of Chartered Surveyors (Rics) said a large majority of surveyors were expecting house prices to rise.
The first phase of the Help to Buy scheme in England started in April, when buyers of newly built homes were eligible for a 20% equity loan from the government on top of their 5% deposit.
Similar schemes are operating in Scotland and Wales.
Under the second phase, buyers only need to provide a small deposit, with the government offering a guarantee of 15% of the loan to the lender - for a fee - to encourage the bank or building society to offer the loan.
Checks will still take place to ensure that those who apply are able to make the mortgage payments. The scheme will be available for first-time buyers and home movers borrowing to buy new and old homes valued at no more than £600,000.
It means a buyer looking to purchase a home costing £200,000 would have to put down a deposit of around £10,000. Demands have been much higher than this for many first-time buyers since the start of the financial crisis, usually about 20% of the value of a home.
Best buys?Prime Minister David Cameron announced at the Conservative Party conference that the second phase of the scheme would be brought forward by three months from January.
Dickie and Heidi Steel say they can save up more quickly for a 5% deposit
A number of lenders have expressed an interest in joining the second phase. Lloyds Banking Group and RBS are the most prominent.
However, it is unlikely that many will be in a position to offer these mortgages in branches or through brokers in the coming days and weeks.
They are expected to outline some of the mortgage rates that will be available. Comparisons are difficult, as there are so few 95% mortgages on the market at present.
The most competitive, widely available two-year fixed rate mortgage, for those offering a 5% deposit has an interest rate of 5.95%, according to financial information service Moneyfacts.
For those able to offer a 10% deposit, the cheapest mortgage deal was 3.54%, with a fee of £1,675, Moneyfacts said.
Price risesAn influential group of MPs has echoed concerns about the potential effect of the Help to Buy scheme. The Treasury Select Committee said that great care was needed from the government when setting up and running the scheme.
"Mistakes could distort the housing market or carry threats to financial stability," it said.
It said that - without care - the scheme could raise house prices, rather than stimulate the number of homes for sale.
"We continue to believe that the government of the day will face strong incentives to extend the scheme, with the attendant risk that the mortgage guarantee scheme becomes a permanent feature of the UK mortgage market," it said.
Last month, Chancellor George Osborne asked the Bank of England's Financial Policy Committee to make annual reviews of the scheme, starting next September.
The committee had been due to make an assessment only after its first three years of operation.
Mr Osborne said that the housing market was recovering from low levels of activity and the latest extension of Help to Buy would help many more people get a foot on the ladder.
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