USPS money order is a good way to go. Ya it might take a few days longer to get to the seller but its probably the safest thing next to credit cards. If the seller defrauds you in anyway since you sent a USPS money order that can turn into a federal crime (since it was through the mail) and the USPS police will come knocking on his door. I use USPS money orders all the time, and I use them mostly when I buy all my firearms!!