To configure the functionality:

1) Go to the admin panel and select the Delivery Methods section:

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2) Create a shipping method using the Add Shipping Method button:

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3) Fill in the following fields:
Name: Shipping Calculator
Gateway: Catapult
Save your changes.

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After that, when placing an order, a new Delivery Method - Shipping Calculator will appear in the basket.

The Buyer's user can log in to his personal account and add the product to the cart:

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To calculate the cost of delivery, you must select the Delivery Method - Delivery Calculator:

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The buyer will be shown a form for calculating the cost of delivery

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After filling in the required parameters for calculating delivery, click on the Calculate button:

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As a result, the user will be shown the results of calculating the cost of delivery by all available options:

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At the end of the list of delivery methods, there is an opportunity to change delivery parameters and recalculate the cost:

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