Wait....if there is "no way" to show customers the cost of shipping using extensions, then how do the customers know what they will pay for shipping? Just learned why I have such a huge abandoned cart number: Squarespace carrier calculated shipping is DOUBLE what I see on USPS and UPS websites. This has been going on for years now and no one said a word to me about it until today. My products are all different sizes, shapes and weights. Flat rate simply does not work. Help! I'm mortifed by this. I need an intelligent solution that does not leave me eating shipping costs, but does not drive my customers away.