For me as a parent, we paid tuition for 6 semester - Equivalent of BYU/BYUI tuition.
Freshman year - BYU/BYUI Tuition only and no car.
Post Mission, BYU/BYUI tuition only and given a reliable used car that become theirs
If they got below a 3.0 at the end of a semester, they were then expected to pay for their own tuition the next semester. If they got a 3.0 that next semester, we would then pay the next semester.
My kids were responsible for their housing, food and activities - so they each had a part-time job
We paid their car insurance, stayed on health insurance and cell phone bill until they graduated.
Three kids went to BYU/BYUI and now my youngest is a Freshman at Mississippi State on a full soccer scholarship (out of state tuition, housing, food + $6500 stipend)