The calculation of the order's shipping costs depends on whether the customer has already chosen a shipping method for the order or not. In MyCashflow's default theme, customers see the shipping costs during the shipping method selection phase.

When customers have added products to the shopping cart but have not yet selected a shipping method, the calculation of shipping costs is based on the online store's default shipping method and the order's weight. The default shipping method is the one at the top of the list on the Settings > Shipping methods page.

See instructions on how to rearrange shipping methods.

When the customer has selected a shipping method, the calculation of the order's shipping costs is based on that and the order's weight.

Also read about the settings that affect the display of shipping methods at checkout.