At the time and place fixed for such hearing, such person shall have an opportunity to be heard. The commissioner upon such hearing may administer oaths, examine and cross-examine witnesses, receive oral and documentary evidence, and shall have the power to subpoena witnesses, compel their attendance, and require the production of books, papers, records, correspondence, or other documents which the commissioner deems relevant to the inquiry. The commissioner, upon such hearing may, and upon the request of any party shall, cause to be made a written or electronic record of all the evidence offered or introduced and all proceedings had at such hearing. Nothing contained in this chapter shall require the observance at such hearing of formal rules of pleading or evidence.