NEW YORK (CNNMoney.com) -- Home prices are cheap. Affordability is at a record high. And the market is littered with distressed properties looking for a buyer.

But there is one big obstacle for many first-time house hunters looking to take advantage of the market: cash for down payments. The typical first-time buyer has only saved enough to cover 4% of the purchase price, according to the National Association of Realtors.

As part of the stimulus package, Congress created a refundable first-time homebuyers tax credit in hopes of helping on-the-fence buyers to take the home-purchase plunge. But buyers couldn't collect the $8,000 credit until tax time, rather than at closing time - when it's needed.

Now the U.S. Department of Housing and Urban Development is planning to change that. The agency is working on a plan that will allow Federal Housing Authority-approved lenders to provide buyers with the tax credit cash up front.

"We all want to enable FHA consumers to access the tax credit funds when they close on their home loans so that the cash can be used as a down payment," said Shaun Donovan, HUD secretary, in a speech last Tuesday before the National Association of Realtors.

Donovan did not reveal many details, but the plan could be modeled after programs in Colorado, Missouri, New Jersey, Pennsylvania, Tennessee and Washington. To quickly infuse cash into their housing markets, these states created "bridge loans" that allow buyers to borrow against the $8,000 credit and then repay it with their tax refunds.

The first state to launch such a plan was Missouri, which rolled out its Missouri Housing Development Commission Tax Credit Advance Loan program on January 14 - a month before Congress approved the stimulus package. Since then, Missouri has approved applications by more than 300 borrowers and closed on 128 of them.

Lamar Cherry and his wife, Chrishanna, used the program to augment their down payment when they bought their home in Kansas City.

The couple purchased a four-bedroom, three-bath split-level home for $150,000, putting about 6% down. Much of that $9,000 came from the loan program, which they tapped so they wouldn't have to drain their reserves.

"We had money saved up that we were going to use for the down payment," said Cherry. "Now we can use some of that to buy some things we need for the house."

At closing, the Cherrys, like all buyers in the program, signed for their first mortgage, plus a second mortgage issued by the state. The second note is good for 6% of the price of the home, up to $6,750; there is a $350 set-up fee, but no interest is charged if the debt is repaid by June 2010.

In Missouri, borrowers can only access $6,750 of the $8,000 credit for down payments. "We wanted them to have a cushion below that $8,000 in case other tax liabilities show up," said Greg Spurgeon, the single-family homeownership administrator for the Missouri Housing Development Commission.

If borrowers don't pay off the note, it becomes a 10-year fixed-rate mortgage with an interest rate one-half percentage point above that of their first mortgages. For example, borrowers paying 6% on their first mortgages would be charged 6.5% on the second.

So far, Spurgeon said, a significant proportion of participating homebuyers have repaid their loans. He expects most of the others to do the same before the deadline.

Cherry has claimed the federal tax credit on his 2008 taxes, but he hasn't gotten his refund yet. He definitely intends to repay the loan before the 2010 deadline because, he said, not doing so would add about $75 a month to his house payments.