Preview the design of the email that a customer receives after purchasing a product from the store.

At this point, I don't know what an email to a customer would look like after purchasing my ebook, how that ebook should be downloaded by the customer, etc, etc.

The solution addresses Naffy perfectly.
In one place, along with the Title, description, price of the product, there is a window for the title of the message to the customer and an editable preview of the drafty automatically completed with the data entered above.

You can even include a resale offer there.