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There are a number of scenarios in which you may wish to add additional products to the checkout page:
Extra Upsell
You have an upsell product that you want to allow the customer to be able to select directly from the checkout page. For example, an optional shipping insurance. In the following example, the upsell is prechecked. You could change this by removing the checked attribute from the element:
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Code Block <input type="checkbox" value="5" quantity="3" class="kformCheckoutUpsell">
This will show the option to purchase 3 of campaign product 5.
Hidden Charge
You have a hidden charge for an additional product that you would like to pass from the checkout page. This is the same as the checkbox above with the exception that you hide the checkbox from the user by adding the style='display:none' attribute to the checkbox element.
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Code Block <input type="checkbox" style="display:none" checked="" value="[productId]" class="kformCheckoutUpsell">
Free Gift
You need to send a free gift along with a product purchase. This is the same as a hidden charge, the only difference being that you would need to ensure that the price for the campaign product is set at zero.
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