Try to find out the physical address of a seller or caller. With Internet based phone services (VOIP) and other readily available software, phone numbers can easily be "spoofed." This means that bad guys can make any number appear on your caller ID. It's often difficult to determine where they are physically located. Do online searches with the information you are provided and look for reviews. Often, there will be user experiences posted.
Most scammers will insist that you wire money or use prepaid money cards for payment. Often, they receive the money overseas and it is virtually impossible to reverse the transaction or trace the money.
If you notice any charges you do not recognize, contact your bank, card issuer or other creditor immediately.
You should never wire money to sellers who INSIST on wire transfers for payment. If a distant relative claims to be in an emergency and requests wired payment, you should always check with other family members first. This is an often used scam where money is transferred overseas.
Banks are required to make funds deposited from checks available within days, but uncovering a fake check can take weeks. You are responsible for the checks you deposit and are often responsible for paying back to the bank. Someone who overpays you with a check is almost certainly a scam artist.
Whether the message comes as an email, a phone call, text message or pop-up ad on your electronic device, your information should never be provided. This is called "phishing." Scam artists are trying to trick you into providing this information so that they can create accounts in your name.