Primary risk is associated with reloadable cards that can carry higher balances. You can mitigate your risk by establishing card limits that make they unattractive for use by money launderers.
Your service provider should be able to offer multiple surveillance options such as monitoring for credit balances, common usage sites over a specified dollar amount, multiple source credits, multiple purchases of cards by same person, etc.
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Life without Jesus is like an unsharpened pencil - it has no point.