An applicant’s share of eligible costs incurred must not be less than 25 percent. The substantiated value of donated materials, equipment, services, and labor may be used as all or part of the applicant’s share of eligible costs, subject to the following:

(1) all items and sources of donation must be indicated on the application and any supporting documentation submitted to the commissioner;

(2) the rate for calculating the value of donated, nonprofessional labor is the prevailing federal minimum wage;

(3) the value of donated equipment may not exceed the highway equipment rates approved by the commissioner of transportation; and

(4) the value of donated materials and professional services must conform to market rates and be established by invoice.