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You can change the total price of the product depending on the quantity of products your customer buys, the user group, the country, etc. This is done with the "Specific prices" section of the "Prices" tab. Click on the "Add a new specific price" button to reveal the creation form.
Priority management
A customer might fit into multiple prices or discount rules, even when you have set detailed prices and quantity discounts, with custom groups and shops (if in a multistore context). PrestaShop therefore uses a set of priorities in order to apply a single price rule to such customers. You might want the user group to be more important than the currency, for instance.
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