Tricky question.. here are some guidelines to follow when looking for a scam. At the bottom is a list of numbers/websites to use to report a scam. Maybe they can help you determine the legitimacy of a breeder.
Buyers who claim to be traveling abroad and offer to have their "agent", "business associate", "friend", or "shipper" complete the transaction. They may offer to pay by Cashiers Check for over the amount. This 'buyer' will claim to be trusting you to return the overage of funds. Banks will often cash these checks then hold you accountable for the funds once the check fails to clear.
Sellers who insist that you use Western Union or other money transfer services.
Sellers who reside in distant countries. Sellers that request money to be wired to Romania, Ukraine, Macedonia, Belarus, Pakistan, Russia, Lithuania, Egypt, Lagos, Nigeria, Colombia, Malaysia, Indonesia or Cameroon. tend to have a very high incidence of fraud. Unless you have a lot experience with international orders, you may want to decline to send money to these countries.
Sellers offering a Dog significantly below market value. This is often a scam to engage many people to send money for this non-exsistent dog. You will never receive the dog.
Sellers who request that a "shipper" be paid directly or sellers that state the Dog will be delivered directly to your door or destination. All Dogs shipped via an airplane must be picked up at the airport.
Sellers who state that you must send additional funds to get the Dog through customs.
Seller insists that you use an online escrow service other than Escrow.com. Before using any escrow service verify the company with the Better Business Bureau to insure the business has a satisfactory record.
Who should I notify if I suspect fraud?
FTC toll free hotline: 877-FTC-HELP (877-382-4357)
FTC online complaint form (www.ftc.gov)
Internet Fraud Complaint Center (www.ifccfbi.gov)
Internet Crime Complaint Center (www.ic3.gov)