Price calculation

Hello, I’m trying to figure out how to use the price calculation and how to reference choices from other layers.

What I want to do:

If a customer checks a box, a flat rate fee is applied + an additional amount based on the amount of drawers selected. (an extra $13/drawer). I’m not sure if there’s a way to use conditional logic to accomplish this, or if “if” statements can be used with the price calculation feature. I don’t know the syntax, so it’s very hard to figure out how to accomplish this task.

Any help would be appreciated.

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