Ever since the housing market took a dive, foreclosure scams have been spreading like wildfire. And that's not about to change, what with some 4 million homeowners currently delinquent on their mortgages and another 1.6 million already in the foreclosure process.

What is changing, though, is the age of people being targeted in so-called rescue scams, in which you're promised help in hanging on to a property threatened with foreclosure.

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Foreclosure scam impacts Imogene Hall. — Photo by Carl Juste/Miami Herald/MCT via Getty Images

In the first six months of this year, more than 40 percent of all reported victims were 51 or older, up from 36 percent in July through December 2010 and 26 percent from October 2009 to June 2010, according to a report by the Lawyers' Committee for Civil Rights Under Law, a nonprofit advocacy group.

Since February 2010, this age group's losses have exceeded $16 million, averaging $3,358 per victim.

Typically, the losses come in the form of upfront fees paid to scammers who get in touch after learning of a foreclosure from newspapers, specialty publications or public records.

Among many other sins, they generally ignore federal rules that forbid foreclosure assistance or loan modification companies to collect fees until the lender has agreed to the relief in writing.

Here are six schemes scammers use to rip you off:

1. Lawsuit lures. In the latest variation, you receive a letter inviting you to join a class action lawsuit against your mortgage company. This bogus offer is made more believable by the widely publicized "robo-signing" scandal of last year, in which lenders were accused of hiring unqualified people to falsify foreclosure paperwork en masse.

In these letters, reports the FBI, you're told that you can be a plaintiff in what's known as a "mass joinder" lawsuit — but only if you pay a nonrefundable upfront fee of $2,000 to $5,000. In reality, class-action attorneys are typically are paid only after the case is over, and only if they've won.

2. Phony counseling. For an upfront fee of hundreds or thousands of dollars, self-proclaimed "experts" (they may claim to be lawyers) say they can negotiate a deal with your lender to reduce your mortgage payments or save your home.

On top of the fees, these counselors may insist that you make mortgage payments directly to them while they work out the promised deal with your lender. After several months of collecting, they disappear.

3. Phoney forensic audits. Crooks offer to review your mortgage documents to determine whether your lender complied with state and federal laws. The claim is that the resulting "audit report" will help you avoid foreclosure, speed up a loan modification or reduce or even forgive your mortgage. "Nothing could be further from the truth," says the Federal Trade Commission in a consumer alert.

Next: Don't fall for the "sign here" shuffle. >>