Check washing is still alive and well. Clark never writes checks anymore because of the dangers inherent in doing so, but he knows that many people still do. Check washing gives criminals a very low-tech way to steal money. It involves using a solvent to erase the payee info on the check and change it, along with the dollar amount. So Clark advises people not to put their bill payments in their home mailbox and raise the flag on that mailbox. That's a signal to criminals to come around for some easy pickings. Instead, you should drop your bills paid by check in a secured mailbox, whether it's a locked box or a USPS drop box. Another way to avoid having your checks washed is to use a pen with wash-proof ink. These kinds of pens are available at most office supply stores.

Businesses are at an even greater risk than individuals when it comes to check washing. That's because they usually have more cash in an account than an individual. Additionally, business accounts are subject to more stringent requirements. For example, if there's a break-in at your business and your checks are stolen by a thief, you can be held responsible for part or all of the losses you may incur through check washing. That's why all businesses need a locked cabinet or a safe to store their checks. Likewise, if you use computer-run checks and you leave blanks in the laser print, you're fully exposed to liability. So if you're a business owner, you must lock up your checks securely at night. One more caveat: a dishonest employee can do the same damage to you as an external thief if they get hold of your business checks. So protect yourself from internal threats, as well as external ones.