Down-payment assistance looks like peanuts compared to this.

According to a story in Saturday's Wall Street Journal, the FBI is examining builders' use of generous and unexpected sales incentives such as paying off buyers' credit cards and car loans.

"Using incentives to sell homes has long been a marketing tool for builders. When properly disclosed and structured, the practice is legal. But the Federal Bureau of Investigation is looking into allegations that home builders, brokers and appraisers defrauded lenders by not disclosing unusually large incentives to buyers, which could have added as much as $100,000 to the price of a home."