Cartfuel.io is a web form builder that allows you to easily accept payments for your product and create upsell funnels.
You can set up one-click upsells as part of your payment process. After the customer purchases your product, you can add an upsell that allows the customer to purchase with just one click. For example, if you are selling an email course, you can add-on coaching services.
You can only create a form for one product at a time. This is not a "shopping cart" where you can have the customer add multiple items to check out (other than upsells).
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