The parents do not need to give the student much financial information beyond a clear statement that “we can give you $x (per year or total) for your college costs without needing to take parent loans or you needing to take loans that require a cosigner, and this amount will not endanger our other financial goals like retirement or your younger siblings’ college”.
Basically, reasonable assurance about how much they will fund, rather than “we’ll try to make it work” or some other answer that creates worry about family finances. Yes, $x could be $0, which still gives the student useful information to make a decision with.