The commission may employ temporarily such experts, engineers, and inspectors as may be necessary to supervise changes in existing crossings undertaken under this chapter; the expense thereof shall be paid by the railroad upon the request and certificate of the commission, said expense to be included in the cost of the particular change of grade on account of which it is incurred, and apportioned as provided in this chapter.

The commission may also employ such engineers and other persons as permanent employees as may be necessary to properly administer this chapter.