(a) The engineer selected by the applicant, in making a proposal to the applicant and the commissioner to furnish engineering services required for the proposed comprehensive study and report, shall propose a total fee for his services. The basis for the fee shall be stated.

(b) The proposed fee for engineering services shall be based on:

(c) Any municipality subject to approval of the commissioner which maintains its own engineering department to perform such engineering services may base its estimate of the cost for making such a comprehensive study and report on the audited costs of performing similar services for similar previous studies made by such municipality proportioned according to relative size and scope of past studies in relation to those of the proposed study. It shall not include payment for indirect administrative, legislative or overhead costs.

(d) Such proposal for total engineering fees shall include the estimated costs for test borings and other special services which may be required. Such cost shall be listed separately in detail.

(e) The commissioner has the final responsibility to determine that the fees proposed are reasonable and conform to good practice.