(1) In ascertaining the value of the gas system, the court of condemnation shall have full power to summon witnesses, administer oaths, take evidence, order the taking of depositions, and require the production of any and all books and papers deemed necessary for a full investigation and ascertainment of the value of any portion of the gas system. When part of the gas system appropriated under the Municipal Natural Gas System Condemnation Act extends beyond the territory within which the city exercising the power of eminent domain has a right to operate the gas system, the court of condemnation, in determining the damages caused by the appropriation, shall take into consideration the fact that the portion of the gas system beyond that territory is being detached and not appropriated by the city, and the court of condemnation shall award damages by reason of the detachment and the destruction in value and usefulness of the detached and unappropriated property as it will remain and be left after the detachment and appropriation. The court of condemnation shall have all the necessary powers and perform all the necessary duties in the condemnation and ascertainment of the value and in making an award of the value of the gas system.

(2) The court of condemnation shall have power to apportion the costs of the proceedings before it between the city and the utility and the city shall provide for and pay the costs as ordered by such court. The city shall make provisions for the necessary funds and expenses to carry on the proceedings of the court of condemnation while the proceedings are in progress. If the governing body of the city elects to abandon the condemnation proceedings, the city shall pay all the costs made before the court of condemnation.

(3) If the services of expert witnesses or attorneys are secured by the utility, their fees or compensation as billed to the utility are to be taxed and paid as costs by the city to the extent that the court of condemnation determines that the fees and compensation sought (a) reflect the prevailing industry or professional charges for such services in cases of the size involved in the condemnation and (b) were reasonably necessary to a just and accurate determination of the value of the gas system. The costs of any appeal shall be adjudged against the party defeated in the appeal in the same degree and manner as is done under the general court practice relating to appellate proceedings.