This is of course a family decision, and not an easy one.
One issue is that the majority of students do not graduate in 4 years. If your child goes for a 5th year, they will still be in-state in Florida. There are many reasons to go more than 4 years. One example that is very common is a late change in majors. One reason that applied to us is a child who decides to double major and only completes one of their two majors in the first four years. If you are going to run out of money after 4 years then this might not be possible. Sometimes students have a bad semester which leaves them a course or two short and requires another semester. Sometimes students in tough majors are better off taking four courses at once rather than five.
Many students end up going to graduate school. It is a lot easier to afford graduate school if you don’t use up your college funds for a bachelor’s degree.
Also, UF is a very good university.