We do this with drug reimbursement costs and construction already and I’m pretty sure those for-profit companies would also disagree on what the limit should be. I also don’t think it needs to be a one-size-fits all threshold; it could be adjusted to COL and/or job prospects that are tied to graduate statistics. IMO that goes a long way to aligning the incentives of the student and the institution.

I’m curious if you have an alternative solution

Personally I think limits (and significantly higher grants to make student loans unnecessary for a basic post-secondary education) are needed. But I think it's worth recognizing that limits will make what's already a very divisive issue, even more divisive...

I have seen other pilot programs. I think it was Purdue who was considering "buying stock" in students, where the student would pay a portion of their income for a certain number of years in exchange for a scholarship.