Looking for suggestions on how to hide less expensive, "Renew" memberships

I have ProtectedContent, but I may add another if needed.
I have a product (audios, videos, and PDFs) that has a high initial payment ($500), but will have inexpensive ongoing membership access ($35/yr).
Some, or all, of the content will be in both memberships. I don't want to give access to the $35/yr content until they have purchased the $500 initial membership.
Do you have a suggestion?
I considered having a Subsite: The would pay $500 on the main site and have access to the main site content. They would also have access to a menu button that would link them to the subsite content and memberships.
I would manually add them to a private membership on the subsite. EVERYTHING (incl. membership pages) on the subsite would be protected until I add someone manually. The subsite would be the only place where they could purchase $35/yr memberships.

As a product suggestion, I would like to have membership levels that give access to other membership options, because this would solve my problem simply.

My present solution seems a bit convoluted. I would rather not have a subsite. Is there a better way?