Paypal web services allows you to specify a shipping rate when adding items to the cart by specifying an hidden input with the name set to shipping and the value set to the amount. The problem is that this doesn’t work when you are using hosted button’s which have shipping details already saved. Try it yourself. Set up a hosted button and then try using <input name=”hosted_button_id” type=”hidden” value=”abcdefghji”> and <input name=”shipping” type=”hidden” value=”0.0″> within the same form. You’ll find that the shipping input will be ignored and the settings you have setup in the hosted button will be used. So what is the solution?
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