One of the older scams is something called check washing. It involves thieves taking letters, often outgoing mail left unattended in mailboxes, but some can even snatch letters from Post Office collection boxes.
Then, use something as common as the acetone in nail polish remover they are able to remove the name on the “Pay To” line as well as the amount of the check, leaving the original signature untouched. Then, they’re free to write in whatever amount to whatever payee they want.
How can you protect yourself from this scam?
1.) Use online payments – The best and simplest solution is to pay for what you need online. Most banks offer this service for those who have check accounts with them. Also, many utilities, insurance companies and other vendors offer amount online paying services. This way, there are no paper check to steal.
2.) Deposit your mail directly at your local post office – Go inside the building and make your deposit there. Use the drop boxes outside the post office may not give you the security you imagine. We have seen those boxes so stuffed right before collection time, that anyone could grab a handful of mail without any special effort or equipment.
3.) Use non-erasable ink.
4.) Monitor your bank account and report any irregularities quickly.