Manage add-on (additional fee for option)
Objective:
Add-on feature will help you add extra fee for options customer choose

Step by Step Guideline:
In Option Sets editing, click on the Option you want to add an additional price

Choose "Extra fee" on the Add-on and fill in the price for each option value

Click Save the option set and Recheck on the product page. When selecting the option has price add-on, it will add additional price

If you want the total product price to increase when choosing the option add-on, you can install "Show updated total price with add-ons" in the Advanced features:

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