Some con artists look to profit from tragedy. They come out of the woodwork following a natural disaster when you could be at your most vulnerable. According to the National Insurance Crime Bureau, a non-profit that educates people about insurance companies and insurance fraud, it's common in the aftermath of a disaster for local professionals to go door-to-door to offer help in clean up or to repair damage.

But, buyer beware: While many of these contractors are reputable, some aren't. Unscrupulous businesses (or individuals) use various schemes after a natural catastrophe strikes a region. Some of these include overcharging, pocketing upfront payments without doing the work, using shoddy or cheap materials or trying to scam people out of their insurance companies' claim checks.

How to avoid con artists after a disaster If you're the victim of fire, earthquake, flood or even an oil spill, make sure you take these precautions before you hire a contractor to clean up the mess:

1. Get two (or more) estimates.

2. Get all repair work in writing and have it signed by the contractor. Ask specific questions about the cost, work detail, time schedule, guarantees and payment schedules. Also, never sign a contract with blanks -- a common scheme is for the con artist to add unacceptable terms after you sign.

3. Ask for references and call them to confirm other customers' experiences with the contractor.

4. Ask for the contractor's driver's license number and write down his license plate number. You'll need this info if they skip town with your money.

5. Don't pay in full until the work is finished and inspected by code enforcement officials in your town (if applicable).

6. Be wary of contractors who try to explain your insurance policy and what it covers. Beware of being talked into fabricating an insurance claim. When in doubt about what is covered in your policy, contact your insurance company directly.

If you think you've been conned or approached by an unscrupulous contractor, contact the NICB at 1-800-835-6422. You can also use your cell phone to text any information to TIP411 (keyword "FRAUD"). You have the option to stating your name or remaining anonymous.