But in many cases, agents and loan officers say, first-time buyers are receiving loans insured by the Federal Housing Administration, which allow for lower credit scores and a down payment of only 3.5 percent.

Unlike the subprime mortgages doled out a few years ago to nearly anyone who asked, F.H.A. loans include strict income requirements. Buyers must document two years of employment history with pay stubs and W-2 forms that are verified by the underwriter, and they can typically borrow only around 31 percent of their income, or 43 percent when other debt is included.

Andrea Heuson, a finance professor at the University of Miami, said the tighter restrictions should help ensure that people who buy can afford to pay what they owe  as long as they keep their jobs.

Image Tiffany Munro and her mother, Taina Goldman, in the dining room of their new home. Credit... Maggie Steber for The New York Times

A second risk is that these new buyers will walk away if property values continue to drop.

Jennifer Vaughn’s development in Homestead is one of many where prices seem to fall by the day.

A 26-year-old first-time buyer, Ms. Vaughn closed on a three-bedroom, three-bathroom townhouse in November, paying $87,000 for the foreclosed property with an F.H.A. loan. The price was far below the $261,000 the house sold for in October 2006, but a few weeks ago, a townhouse with the same layout and fancier features sold for $75,000. And a third is about to close for $65,000, said Andy Lopez, a real estate agent at Keyes Company Realtors who found Ms. Vaughn her townhouse. So already, she appears to owe more than her home is worth. Not that she minds.

“I’m going to stay for five or six years at least,” Ms. Vaughn said, “and I’m sure prices will go up somewhat by then.”