@icantgiveup, the OP is looking at $92,000 in debt- vs no debt. Your son is looking at $28,000. A lot, but a small fraction of what the OP would be committing to. You may not have heard of Pitt, but it is a very strong school, and particularly strong in the biological sciences. Employers and grad schools will know it.
It is unlikely that he can borrow that much, but even if he could an undergraduate biology degree is just not worth that much debt- especially when there is a very strong alternative. Biology undergrads are 10 a penny these days, and the jobs where you can earn enough to pay off that amount of debt require further qualifications. That much debt will be a significant limitation on what options the OP has.
Berkeley is an excellent school, but so is Pitt, and for undergrad bio the difference of nearly $100K is absolutely too much debt.