So we pickup the little stuff from Amazon, using a special account just for resell qualified items for sales tax exemption.

Since the recent sales tax law change (Dec 1st, CT and many other states), I've just found a couple qualified items (and in the past, properly exempt purchased items) got sales tax added anyways now.

After chatting with Amazon; vendors have the option to control this, most allow Amazon to do the clearance, for those who don't you have to afterwards contact Amazon for a sales tax correction, you can request up to 1 year from ship date.

You might want to check your recent orders, and watch your cart.