(1) The commission due the commercial agent is to be calculated by the trader on a monthly basis; this period may be extended to a maximum of three months. The calculation is to be effected without undue delay, at the latest by the end of the following month.
(2) Upon calculation of the commission due, the commercial agent may demand an extract from the books concerning all business and transactions on which they are entitled to a commission under section 87.
(3) The commercial agent also may demand information regarding all matters that are material to the entitlement to a commission, its due date and the calculation thereof.
(4) If the extract from the books is refused, or reasonable doubt exists as to the correctness or completeness of the calculation or of the extract from the books, the commercial agent may demand that, at the trader’s option, either the commercial agent or an auditor or sworn certified accountant to be designated by the commercial agent be permitted to inspect the business records or other documents to the extent necessary to determine the correctness or completeness of the calculation or of the extract from the books.
(5) These rights of the commercial agent cannot be precluded or limited.