The Shipping Wizard tool is synced to the actual shipping service's computers to get their rates in real time. Thus, it automatically and instantly updates to reflect any rate or service changes that a shipping carrier has made. It does the legwork for you!
Determined After Checkout is no longer a shipping option available to US based shops.
For large items which require specialist packing and transport, the Freight option may be selected, and then the shipping can be calculated by the shop owner after the buyer has submitted the Purchase Order.