This short video sets up a Dynamic Pricing Build-A-Box, where shoppers pay for each product they pick: naming the box, choosing the subscription plans it draws from, adding a tiered discount, turning it on, setting the limits and the redirect, and saving it. Then it shows the box on your store, at checkout and in the customer portal.

The step-by-step version, with every setting explained, is in How to set up Build-A-Box.