Sales plans

One course can be sold several different ways.

The sales plan list — access scope, price and term for each plan

Common combinations

Plan	What it unlocks	Good for
Single chapter	Specified chapters	Letting people test the water
Full course	Every lesson	Your main offer
Subscription	Every lesson, billed monthly	Courses whose content keeps growing

Each plan gets its own price, term, and whether it includes a certificate.

Question: A student bought a single chapter and now wants the full course

Create an upgrade for the difference plan, and the system deducts what they've already paid.