The financial affairs of each sub-district shall be handled as a unit and in accordance with the provisions of title 25 of this article which apply thereto. Compensation of the members of the board, salaries of regular employees of the regulating district, together with expenses and general operating costs shall be allocated by the board on a time basis among the sub-districts and paid from district funds. Such payments shall not operate to change the status of any member, officer or employee, nor shall they result in an increment in the rate of payment made to them, computed on an annual basis. Preliminary costs incurred in the formation of a sub-district shall be reimbursed from sub-district funds if the sub-district is formed; otherwise they shall be a charge against the signers of the petition. Funds raised under the provisions of title 21 of this article cannot be used in connection with any river or drainage improvement district or sub-district.