In this tough economy, builders would rather give stuff away than sit on unsold homes and condos. And that's great news for new-construction homebuyers.

Rhonda Duffy, owner of Duffy Realty in Atlanta, says a builder's whole career could rest on whether he or she sells one house.

"Builders used up all their construction loan money, and they're sitting on properties. So they can't build any more houses because they've got to sell these first," says Duffy.

These desperate times translate into 5-percent to 20-percent discounts immediately off the asking price, says Jason Pohlonski, owner of Pohlonski Real Estate Investments in Chicago. Later in the year, prices could drop to 40 percent below the original price, Pohlonski says.

The seller's concessions don't stop at the asking price. Brian Lewis, executive vice president of Halstead Property in New York City, says it's been more than a decade since buyers have felt this kind of power, and they're using it to score great deals. "They are not necessarily falling in love with homes. They are falling in love with deals," Lewis says.

Some experts say the freebies are built into the price. Nonetheless, Lewis says, "Ask for everything you want."

Here's a look at what builders might be willing to pay for or add.

Appliances and upgrades: Upgrades on appliances are probably the best way to add value to new construction, and some builders are footing the bill, Pohlonski says. "They will upgrade to nicer marble, better appliances, hardwood floors and better cabinets," he says. Developers will add built-in microwaves, freestanding ranges, cooktops, dishwashers, refrigerators, and washers and dryers, says Cindy Stuart, a Realtor with Semonin Realty in Louisville, Ky.

But sellers might not always be willing to pay for them, Stuart says. Rather, they will offer the appliances at cost and do free installation. "Builders get appliances a little bit cheaper, so you get a good price," she says.

Vacations: Some developers are offering a free vacation to entice buyers. "Vacations are great incentives, especially in the Midwest, where it's cold and dreary all the time," Pohlonski says, noting that builders buy the all-inclusive vacations or cruises in bulk to popular destinations such as the Caribbean islands, Cayman Islands and Mexico. "A five-night stay in Cancun would cost an individual a lot more money than developers can get in a wholesale deal, so there is actually some value there for the buyer," Pohlonski says.

Cars: Many developers are enticing buyers with cars. "I saw a newly built condo building owner give a buyer an E-Class Mercedes on a two-year lease," Pohlonski says. Laurie Donofrio, a Coldwell Banker Realtor in Raleigh, N.C., has encountered developers giving away new Jeep Wranglers. But these were promotional offers used to lure buyers, not the result of a customer request, she says. "A free car can drive a lot of traffic for a seller," Pohlonski says. "Developers just use the car as an incentive, but I haven't seen anybody ask for that."

Closing costs: Depending on how desperate they are, builders could pay all closing costs, transfer taxes and attorney fees, Lewis says. In fact, they are more likely to pay closing costs than to add new products to the home. "Developers want to hold as much power as possible because in this information age of blogs and text messaging, if one person gets one thing, the whole world knows about it in 10 minutes," Lewis says. "They can better control a monetary transaction, like closing costs, than upgrades."