But it isn't fraud - you sent them cash. The end. You can take them to small claims court if they failed to fulfill a contract, but there are a lot of reasons

But it isn't fraud - you sent them cash. The end. You can take them to small claims court if they failed to fulfill a contract, but there are a lot of reasons why a person won't, or can't fulfill their end of the bargain other than criminal fraud. This is why credit cards are awesome for this sort of thing - chargebacks.