The 40,000,000 plus illegals are housed somewhere - be it apartments, hotels, or rental homes. When they occupy 20 percent of NYC hotel rooms, guess what, the price of the remaining supply goes up - so Americans pay twic.e
If they are in apartments, again, the supply is decreased and big Landlord gets higher rents. With higher rents, people say why don't I buy a home for same price? Bottom line, get rid of the illegals and housing/apartment/hotel pricing pressure decreases.
Not every illegal lives in the streets of LA.