You can have whatever definition you want. But for me, working class means just that - a person that has earned their bread through the work of their own hands, not through the exploitation of the labor of others, through rent-seeking, or from inheritance.

I'm sure you can cite plenty of theory, but frankly, I don't care. I prefer a definition of the term centered in lived experience. If you go off raw wealth, you just end up classifying entire nations as working class or bourgeois, at which point the term loses all meaning.