You may notice that the rates you have specified in your Paypal account are different to those in your SupaDupa store, or that your customers have been charged shipping TWICE, once by PayPal, and once by SupaDupa.
This can occur if you have some Shipping Rates setup in your PayPal account for a different service, your PayPal is not configured correctly, and does not permit SupaDupa to be in complete control of your shipping rates.
The following article describes how to set your PayPal "Postage Calculations" to be overidden by the shipping tariffs you have set using the SupaDupa shipping feature.
By doing the following you will avoid customers being charged shipping tariffs that are different to those you have specified in your SupaDupa backoffice.
All you need to do is enable Transaction-Based Shipping.
This can be done as follows:
1. Log in to your account at http://www.paypal.com.
2. Go to My Account > Profile > My Selling Preferences
3. Under the section "Posting my items" click to update the "Postage calculations"
4. On the Postage Calculations page, check the box at the bottom of the page that says "Click here to allow transaction-based postage values to override the profile postage settings listed above (if profile settings are enabled)."
Save Changes and you are done.
From now on Paypal's Postage rates will be overridden by whatever you have specified as your tariffs in SupaDupa.