Again, by spending less than the median housing cost, ideally by spending no more than a third of the median housing cost.
Eg. The median rent in Chicago is about $2K\mo right now. But you can live an more economically depressed part of town and get a one-bedroom for $1.1K or a three bedroom for that same $2K and split that with two roommates.
I'm not OP and her proposal isn't perfect, but this particular critique just doesn't hold water when she specified the median housing cost.
Chicago, I'm a waitress myself and support a family of five here on that income.