Colorado Attorney General Phil Weiser and federal regulators filed a joint lawsuit against the largest apartment owner in the country on Thursday, accusing it of intentionally misleading tenants about the cost of its rentals.

U.S. property management company Greystar swindled renters across the country out of hundreds of millions using deceptive advertising and hidden fees, according to a lawsuit filed Thursday by the U.S.

The complaint filed Thursday charges that the country’s largest landlord failed to include information about numerous mandatory fees in its listings.