The Council shall annually appropriate a sum of money from the general funds for the payment of the expense of the Plan and Zoning Commission. The Commission shall have full, complete, and exclusive authority to expend for and on behalf of the City all sums of money so appropriated. Gifts, donations or payments which are received by the City for planning and zoning purposes shall be placed in such fund to be used by the Commission in a manner appropriate for its purpose. The Commission shall have no power to contract debts beyond the amount of its income for the current year.