Unsolicited home improvement. An individual or pair goes door to door selling repairs that they claim are needed right away, such as a roof repair. Once the work is done, the victim finds that the bill is much higher than quoted or that the work was done with inferior materials. These repairs can lead to other types of theft, with workers going inside for a drink of water and stealing valuables.

Home loan scams. The two biggest scams making the rounds are loan modification scams and forensic loan audit schemes. With home equity virtually nonexistent for a large percentage of the population, scammers are targeting owners' cash, rather than title, says Annette Kirkham, senior attorney at the Fair Housing Law Project in San Jose, Calif. And often, they're going to senior centers to find their victims, she says. Loan modification crooks offer to help seniors renegotiate their mortgage and lower their payments for an upfront fee. However, they usually take the money and do nothing in return.

Forensic loan audits require more money upfront -- often from $10,000 to $50,000. These audits are supposed to uncover fraud in the loan-origination process, thereby allowing the unscrupulous attorney to file a suit forcing a modification. However, that doesn't happen, and the individual winds up losing his money.

Power of attorney scams. These are the most insidious plots, because they typically involve someone close to the senior. They involve assigning legal authority to another person to manage someone's financial affairs. Sometimes it's done willingly; other times it's done by threats or intimidation.

In the hands of someone trustworthy, these documents can to help an older person manage his or her bills. But they are often used by desperate relatives and acquaintances to drain a senior's bank and investment accounts.

Knock-knock thefts. One of the most popular scams for decades running, these involve simple distraction and theft. Someone comes to the door, posing as someone they're not -- a utility representative, a law-enforcement officer or charity worker, for example. The idea is to distract the victim while the crook (or an associate) ransacks the house, grabbing cash or other valuables.

Sweetheart swindles. A younger person or alleged suitor feigns romantic interest in an older person long enough to establish trust and get his or name on bank accounts and property deeds. The suitor disappears along with the property.

8 ways to prevent elder financial fraud

1. Make it a policy not to buy from or contribute to solicitors. The Women's Institute for a Secure Retirement suggests using the following script with callers or people who knock on your door. "I never buy from (or give to) anyone who calls or visits me unannounced. Send me something in writing."

2. Shred all receipts with your credit card number or other personal information.

3. Never give out any personal information over the phone unless you initiated the call. That includes your credit card, banking or Social Security numbers as well as health insurance or Medicare information.

4. Use direct deposit when you can to prevent checks from being stolen.

5. Know where your documents are kept and what they say. Stay organized and make sure what the literature says jibes with what brokers or representatives are telling you.

6. Check out your broker, and never make a check out to an individual for investments. Write checks out to a company or firm to make sure your money is going where it's supposed to go. You can check out brokers and their firms on securities regulator FINRA's BrokerCheck page.

7. Don't isolate yourself. Maintain connections with others in your community, such as friends, neighbors, clergy or even your letter carrier, so you have people with whom you can share your complaints or suspicions.

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8. Hire an elder law attorney. If you work with lawyer, make sure he or she is a member of the National Academy of Elder Law Attorneys, who have special training in legal issues facing seniors.

And if you suspect that you or a loved one is a victim, experts recommend calling Adult Protective Services immediately.

"The most important message that should come out of this is that you can't stop what you don't report," Blancato says.