That depends on the tariffs of the companies you use to deliver your packets. Can be based on weight, size, destination, options chosen by the customer (by air or by sea, express, specific date and time) and your policy (free above a certain price limit, reduction if via some delivery point and not at home) and of course the company you choose for a particular packet.
If you tell your developer the rules he should be able to implement them.
How can I make shipping cost calculation easy and transparent on my Prestashop store? On which basis the delivery cost can be calculated?

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