Finding automatic-admit-for-stats-that-the-student-has is not all that difficult for a high-stats student (and some of these may have lower admission rates than 70%).
However, finding affordability can narrow the range considerably, depending on family finances. Check net price calculators. Also, check for merit scholarships that are automatic-for-stats-that-the-student-has.
But then the hardest part about finding safeties can be the desirability criterion. Many 4.0 HS GPA students feel like “all of their hard work in high school goes to waste if they attend a non-reach college”, so finding safeties that they like can be much harder than it should be based purely on automatic admit or scholarships that are more available to them than for less accomplished students.