Very rough math, since you're an accountant:
Graduation age: 22
Retirement age: 65
Starting salary (no debt degree): $45,000
Starting salary (debt-financed degree): $49,500
Beginning balance of student loan liability: ($30,000)
Annual merit increase: 2.5%
Discount rate: 8%
In other words, here's what happens if you take out $30,000 of student loan debt in order to graduate from a more prestigious university that will earn you an expected starting salary that's 10% higher than a less prestigious school from which you can graduate debt free.
Break-even occurs at age 28 (nominal dollars) or age 30 (discounted cash flow).
Net lifetime benefit is $323,485 (nominal dollars) or $43,614 (discounted cash flow).