Linking an additional collection to the Paid Plans API payment flow.

I want to create a section on my website where someone can purchase a plan that, for a certain amount of time, they can enter info such as text and images and this would be displayed for all to see on the website. Once the time is up, the data would no longer be available for viewing.

I figured on treating this like a membership so I am using the Paid Plans API and using the tutorial “Using the Paid Plans API for Pricing Plan Ordering and Payment” as a template. Users would purchase a payment plan and, as part of the payment flow, be directed to a form where they would enter text and upload images before the final checkout.

I just can figure out how to link an additional Collection with the text/images data to the payment flow. Or is this even possible?

Thanks in advance.