Why does my product prices differ from the ones on the amazon cart redirect page?

The reason for this is the Price import option. When you set the plugin to retrieve prices from Amazon or other sellers, it retrieves the lowest price available. The problem is that this kind of link (with other price than Amazon) cannot be formed because the Amazon API does not supply that kind of info.

The solution is to use Amazon prices only if you have the cart option activated. The Amazon or other sellers option can be used along with the direct link to the product ( by disabling on-site cart and the 90 days cookie ).