Okay, aside from the idiocy of this idea, why would you build "millions" of homes, when there only 500,000 homeless people? Does she want the homeless to be treated like Bernie Sanders and have four homes each?
Motels in Orange Co. CA that took county money to provide shelter for a common strain of street people had to remodel the rooms to be as austere as prison cells, or they'd be unlivable in short order.
Maybe Omar knows that it will take a string of homes to continually house these people ... and then a string of contractors, under lucrative government contracts, to refurbish them several times a year.