。
My friend wants a car of their own.
Literal
Friend [topic-は] my-car [object-を] wanting.
~がっている is required when describing a third person's desires — Japanese does not allow ~たい directly for someone else's inner state. 欲しがっている ('is showing signs of wanting') conveys observable desire. マイカー is wasei-eigo (Japanese-coined English) meaning 'personal car,' not literally 'my car.'