The multiple-category/payment problem is a tricky one. Here's what BD does with it today:
- When you pick a category, if the category has a fee plan associated with it, you get charged for that amount
- If you pick multiple categories, the plugin charges for each one separately
We understand this isn't what everyone wants, so we're working on enhancements to change it.
Here's what we plan to offer in the future:
- The ability to select a fee plan that offers you the ability to select X categories (and no more) for a single fee
- The ability to select any number of categories for a single fee
- The current behavior of each category gets charged when selected
This is something we're working on for our next major release (after the one about to go out).