Someone also suggested setting up a custom zip code for tax-exampt customers.
For example, the zip code for the customer (assuming you don't NEED to use 9-digit zips) could be 12345-abcd.
Then, set up a tax zone such that any zip code of ?????-abcd would get a tax percentage of 0%.
Of course, you'd have to tell the customer in advance to USE this doctored zip code (although, I suppose you could write a Javascript with a checkbox for tax exempt that would then add the extension to the 5-digit zip before the form is submitted if you wanted to get fancy).
~Barefoot Chris
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