I have read so many topics about magento tax wrong calculation—with no solution. That’s really a shame since version 1.4 to version 1.7, Magento can not calculate simple n% Tax from a product.
I WILL PAY 100$ for a solution (and declaration what is the reason for this) can be used for version 1.7 and 1.8 ! Payment will be done by PayPal.
I see no other way out than to make this offer.