Many publishers will consider requests for discretionary APC waivers by researchers who aren’t eligible for other discount/waiver programs. Publishers may limit the journals for which they will make waivers, including restricting waivers to full open access journals (vs. hybrid journals).
Look for information on the publisher website regarding how to request a waiver. Some publishers require waiver requests at the time of submission, others not until after acceptance of a manuscript.
You will be expected to include supporting evidence for why a waiver would be necessary in your circumstances, which is most often based on ability to pay. A lack of external funding, the inclusion of undergraduate co-authors, and the fact that many publishers consider Berry a primarily undergraduate institution (PUI) are all relevant to making a case for a discretionary waiver or discount.
Your request should also include details of: