I'm building an app that allows to calculate real-time shipping rates during checkout process using CarrierService.
In addition to calculating shipping & handling rates, the service I'm integrating is able to calculate taxes (GST, HST) and duties. To calculate duties, we send HS codes and country of origin specified for a product to our service.
I noticed that Shopify has built-in functionality of duties and taxes calculation. The way taxes are calculated can be changed by enabling a checkbox on the Settings > Taxes page (see screenshot below). However, I can't find any possibility to enable/disable duties calculation after HS codes and country of origin are set.
My question is: If my carrier service is able to calculate shipping, duties and taxes at the same time and display the total amount in the "Shipping" line, is it possible to remove the "Duties" and "Taxes" lines from the checkout page, so the customer doesn't need to pay double amount?