Bank buys a house and lists it at 10% markup, never sells it. Bank buys another house and lists it at 10% markup, never sells it. Bank buys another house and lists it at 13% markup, never sells it. Bank then records an 11% increase in its balance sheet value at the end of the year and uses the money to borrow from the Fed at 5% while buying municipal bonds at 8%. The municipalities tax the real estate to pay for the bonds, thereby enshrining the price of housing in the public record and creating a collective financial incentive to never let these houses get sold for less than their inflated price.
If we ever see a serious downturn in the real estate market (like in '08 or '16) we just flood the market with cheap money again. Lather, rinse, repeat. If you end up with a few ~~ghost~~ investment cities dotting the country, where vacant buildings are piling up at prices nobody can afford... oh well. Maybe the throngs of homeless people should have just worked harder in order to afford them.