Woah, easy there! Eighteen and twenty-four are just in the same region *on paper*! Practically, it's miles apart. :d
With eighteen, I was still in school, but finally allowed to drive and drink everything out there and generally finally could do everything I wanted to. It felt great. Now, six years, a (mandatory) army "career", nearly a bachelor's degree and almost half a country awqay from my parents later I just feel old and look back in envy because everything was much simpler (hotel momma!) back in the days.
Change countries beforehand! If you can't pay for uni for your kids here, the state will practically give him/her an interest-free loan (depending on your income) for the (regular) duration of the studies, the maximum of half of which has to be paid back by the son/daughter later on.
I fortunately don't require that (and the paperwork it brings), my "payback" lateron will just be finding my parents a nicer retirement home than they'd normally get.