NY State Attorney General Eric Schneiderman has issued new policy guidelines that would permit owners of mixed-income residential buildings to sell market-rate units in those buildings, provided they either preserve or increase the number of affordable units permanently.

The new guidelines [pdf] go into effect today, and were first reported by the Times. They affect owners of buildings that receive tax abatements and other subsidies from the government in exchange for discounting 20 percent of their units.

Previously, these owners were unable to sell their buildings until the affordability restrictions expired, which could take decades. Under these new guidelines, owners will be able to turn over the market share units, but must commit to the city that the affordable units remain so permanently—this will hopefully ensure that owners will be unable to de-stabilize affordable units once the buildings are sold. The owners would also have to give tenants in market-share apartments the opportunity to buy their units before selling them off.

Earlier this year, Mayor de Blasio committed $41 billion to 10-year plan calling for the creation of 80,000 new units of affordable housing, along with the preservation of 120,000 other units; he also recently passed a mandatory inclusionary zoning law that would require certain developers to include 20 percent (or more) affordable housing units in new developments. In a statement, De Blasio told us, "This is the definition of government working smarter. We're deeply appreciative of Attorney General Schneiderman for putting new tools in the our hands to preserve affordable apartments in perpetuity. We have set an ambitious affordable housing goal, and this is going to help us achieve it."

Last month, Schneiderman's office teamed up with City Hall officials to back a rent-stabilized tenant in the East Village whose landlord tried to buy out her lease in order to pay off her credit card debt. Both city and state officials argued that the tenant should be protected by rent-stabilization laws, without which the city "would be a metropolis largely consisting of the very rich and very poor." Wouldn't that suck?