This article is for charging users extra amounts for options they select. Examples of this include adding charges for monograms, gift wrapping, or whatever your business logic may require an upcharge for.
The app expects you to have made the extra product ahead of time as a Shopify product. The app will not create the product for you, and doesn't add any extra prices without this product. So for example, in Shopify you would add a product called "Monogram" for $5.00. The product must not track inventory/stock levels.
Once the product is created, continue to the form editor for the field group. In the editor select the field that modifies the price. This can only be applied to Radio Buttons, Drop Down Lists, Checkboxes, Image Pickers, and Color Pickers.
Select the edit gear icon, and then click "Conditional Logic".
Create a conditional logic group. You would use multiple conditional logic groups if you need to perform different actions depending on different field values.
In the "If" part select what your field should be equal to. This can be multiple different values, and can include things it should not be equal to.
Next you select if "Any" or "All" of the rules match. If you select "Any", as long as one or more rules are true, all the actions will be executed. For "All", all the rules must match and be true.
Next are the "Then" line items. These are the actions that will be executed if the rules meet the criteria you created. You would select "Add Product" and find the product you created earlier.
You can name the logic group anything. This is only for administrators to see.
Now when a customer selects the option in question, when they hit add to cart the extra charge will be added to their cart. If they remove the main product or update the quantity the app will automatically fix the extra charge products quantities.
Click below link for a visual tutorial: