Working with pot dealers.
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Much of the $40 million in sales tax revenue Colorado hopes to collect from legal pot sales could be going up in smoke because banks and credit card companies refuse to work with sellers, claims a state lawmaker.

Unless banks can get a clear signal from federal regulators that it is okay to work with pot dealers without running afoul of laws aimed at launderers of drug money, the marijuana trade will remain what it is in Colorado – an all-cash business. State Sen. David Balmer says that makes it ripe for unreported – and untaxed – transactions.