You are making the common mistake of confusing Cost of Attendance (the “sticker price” set by the school) with net cost, which is what each student will need to come up with after financial aid is applied.
At the schools you are asking about, which provide mostly (if not exclusively) need-based aid, the amount of aid you are offered will be directly tied to your need. Better family financials = less need = less aid. How much the need-based aid will change year-to-year depends on how much the family financial situation changes over the previous year.
Thumper gave you some excellent advice – use each school’s NPC with hypothetical numbers to see how the aid offered by the school changes when the data you enter changes.