You would need to configure a Variants line for every possible combination of options, including with/without add-on extras, so that each line defines a total overall price for that particular combination. However, we can only support up to three types of Option that affect price with Variants (you could also enable Variations to add three more options that cannot affect price).
As another alternative, you could create each add-on extra as a separate product, or as a generic add-ons product with each option as a Variant, so the buyer would first select their basic wig options and Add to Cart the basic wig, and then select any add-on(s) they want and Add to Cart those separately. We have no way to require ordering the basic wig product first, but you could post very clear instructions for ordering on your site and just deal personally with anyone who "forgets" to add a wig before they order any add-ons.
