Repeater Fields Multi Level Nested
You can use Elementor Section or Inner Section to make Repeater, Sub Repeater
and Any Elementor Widget to make Add, Remove Button
Conditional Logic: If Acceptance checked, the Section Repeater bellow will be shown
Sub Repeater - Nested
Test with Card number 4242 4242 4242 4242 – 04 / 24 – 242 – 42424
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Tutorial
1. PAFE Form Builder
Example: Below is a procedure how to create a bill calculation.
Firstly, we create a simple form that empowers customers to choose product, size and quantity.

Edit Total field > Content Tab > Fields > Type > choose Calculated Fields.
Next, the control section would be shown as below:


In the Calculation control field, add your mathematic formula. Shortcodes of fields would be used as variables.
After choosing product, size and quantity, Calculated Fields will automatically calculate the total amount.

2. Elementor Form
Please refer to Available Math Functions in Calculated Field