。
I can't afford to own a car.
Literal
I [to-は] car [object-を] have [nominalizer-の] leeway [subject-が] not-exist.
Wait — this is actually 車を持つ余裕がない, but it's rendered as 車を持つ without の nominalizer. The 余裕 ('leeway, means, affordability') takes が for what one has no leeway for. A classic 'can't afford' construction using abstract 余裕 rather than concrete money.