(a) The owner of a building located in a county having a population in excess of 100,000 inhabitants who, directly or indirectly, has collected, or caused to be collected, rentals from an occupant of that building during a period in which the number of apartments or family units in that building exceeded the number permitted for that building by an ordinance of the county in which the building is located, is liable to any such occupant in an amount equal to not more than 3 times the amount of any rentals paid by any such occupant, or in his behalf, after January 1, 1970, together with court costs and reasonable attorney’s fees. If the occupant is a recipient of public aid under Article III, IV, or VI of “the Illinois Public Aid Code”, as amended, in whose behalf vendor payment of the rental was made by the Illinois Department of Public Aid, the Department of Human Services (acting as successor to the Department of Public Aid under the Department of Human Services Act), or a local governmental unit, as the case may be, the liability as herein provided is to the Illinois Department of Public Aid, the Department of Human Services (acting as successor to the Department of Public Aid under the Department of Human Services Act), or the local governmental unit making the vendor payment of the rental.
     (b) For the purposes of this Section:
        (1) “Owner” means the legal or beneficial owner of a