- Understand how the auction works. Some online auctions sites can't guarantee the sellers will keep their promise, or verify that the merchandise is described accurately or even exists. Look for credible sites.
- Check out the seller before you bid. Positive ratings can be pumped up by the seller who "plants" comments or can be lowered by competitors.
- Be careful if the seller is a private individual. Many consumer protection laws don't apply to personal sales.
- Be especially cautious when dealing with sellers in other countries. Physical distance, different legal systems, and other factors could interfere with a smooth sale.
- Beware of “shills.” Sellers can raise the price artificially by recruiting bogus bidders which is illegal.
- Get the name and contact information of the seller. Having the name, location, address, and even phone number can be very helpful when following up after a sale. Don't do business with someone who refuses to give their personal information.
- Be wary of claims about collectibles and other expensive items. A good tip is to print out and save any photos and descriptions of the merchandise for future claims.
- Ask about delivery, returns, warranties and service before you pay. Get a definite delivery time, ask for insurance, and inquire about warranties (especially on electronics).
- Look for information on the auction site about insurance. Some auction sites provide insurance up to a certain amount, others use third-party insurers. Make sure to read the fine print.
- Pay by credit card. By using a credit card, federal law will protect you in case the merchandise was never delivered. By using an intermediary service ask what happens in case something goes wrong.
- Look for bonded sellers. Some sellers can be bonded by the auction site who has researched their business background and credit history and will guarantee your money back if your purchase wasn't fulfilled.
- Consider using an escrow service for expensive purchases that aren’t covered by insurance or bonding. An escrow service takes your payment and forwards it to the seller once you confirm your satisfactory delivery, for just a small fee.
- Try mediation to resolve disputes. Some sites provide a mediation service for disputes among sellers and buyers. All problems aren't due to fraud, some can be just a misunderstanding or failure to hold up their side of the bargain in a timely manner.
- Inform auction sites about suspected fraud. Auction sites will sometimes suspend or remove sellers if there are enough claims about fraudulent activities.
http://www.fraud.org/tips/internet/onlineauctions.htm