(1)    The department, or any deputy, employee or agent appointed in writing, is authorized at any time during the business day to examine the books, records, papers, receipts, invoices, storage tanks and any equipment of any licensee under s. 78.09 or 78.47, broker, dealer, general aviation fuel licensee or other person, purchaser or common carrier, pertaining to motor vehicle fuel, crude petroleum or general aviation fuel or alternate fuels to verify the truth and accuracy of any statement, report or return, or to ascertain whether or not the taxes imposed by this chapter have been paid or to determine the financial responsibility of any licensee for the payment of motor vehicle fuel or general aviation fuel or alternate fuels taxes. The department may redetermine taxes and may allow credits for overpayments due to error. The department may determine any person’s liability for a tax under this chapter on the basis of sampling, whether or not the person being audited has complete records of transactions and whether or not the person being audited consents.

   (1m)   Sections 71.74 (1), (2), (10) and (11) and 71.75 (4) as they apply to the taxes under ch. 71 apply to the taxes under this chapter. Section 71.74 (13) as it applies to the collection of taxes under ch. 71 applies to the collection of taxes under this chapter.

   (2)   The department may hold hearings, issue subpoenas, administer oaths to witnesses, take the sworn testimony of any person and cause it to be transcribed into writing and conduct such investigations as it may deem necessary. If any broker, dealer, general aviation fuel licensee, licensee under s. 78.09 or 78.47, purchaser or common carrier, or any other person refuses access to the books, records, papers, receipts, invoices, storage tanks and other equipment, and if any witness fails or refuses to obey any subpoena or fails or refuses to testify before the department, then the department shall certify the names and facts to any court of competent jurisdiction and the court shall enter such order as the enforcement of this chapter and justice shall require.

   (3)   Sections 71.78 (1) and (4) to (9) and 71.83 (2) (a) 3., relating to confidentiality of income and franchise tax returns, apply to any information obtained from any person on a motor vehicle fuel, general aviation fuel or alternate fuels tax return, report, schedule, exhibit, or other document or from an audit report pertaining to the same.

   (4)   The department of revenue shall inform each requester of the amount paid or payable under ss. 78.01, 78.40 and 78.555 and reported on a return filed by any city, village, town, county, school district, special purpose district or technical college district; whether that amount was paid by the statutory due date; the amount of any tax, fees, penalties or interest assessed by the department; and the total amount due or assessed under ss. 78.01, 78.40 and 78.555 but unpaid by the filer, except that the department may not divulge tax return information that in the department’s opinion violates the confidentiality of that information with respect to any person other than the units of government and districts specified in this subsection. The department shall provide to the requester a written explanation if it fails to divulge information on grounds of confidentiality. The department shall collect from the person requesting the information a fee of $4 for each return.