registration form
https://mdotjboss.state.mi.us/webforms/GetDocument.htm?fileName=4004.pdf
Aircraft based in Michigan for more than 90 days, during a calendar year, must either be registered with the State of Michigan, or have a Claim of Exemption accepted by the Aeronautics Commission.
Fee: One (1) cent per pound of the maximum gross weight or the maximum gross takeoff weight of the aircraft, whichever is greater.
Exemption form
https://mdotcf.state.mi.us/public/webforms/public/4006.pdf
259.76 Registration of aircraft generally.
Sec. 76 (1) An aircraft tied down, moored, hangared, or based within this state and the number assigned to that aircraft by the federal aviation administration shall be registered annually with the commission and a registration fee paid. An aircraft shall not be issued a state registration certificate when it does not have a valid and effective registration certificate as issued by the federal aviation administration or a foreign government.
(2) An aircraft shall be subject to the registration provisions of this act except when it is one of the following:
(a) An aircraft engaged in scheduled passenger service flying in interstate or foreign commerce or in that part of interstate or foreign commerce which is intrastate in character, and operating exclusively under the provisions of a federal certificate issued under 14 CFR Part 121.
(b) An aircraft owned by the United States government.
(c) An aircraft of a resident of another state or an aircraft of a resident of this state that is tied down, moored, hangared, or based within another state, having complied with the registration requirements of that state, and operating within this state for a period of not more than 90 days in a calendar year. This aircraft shall not engage in intrastate commercial activity within this state.
(d) Aircraft owned by or registered to the United States, aircraft or the civil air patrol, or aircraft licensed by a foreign country with which the United States has reciprocal relations. This aircraft shall not engage in commercial activity within this state.
(e) An aircraft which, in the opinion of the commission, is in a condition that would reasonably preclude its operation during the registration period.
Look carefully at this:
https://www.michigan.gov/taxes/0,1607,7-238-44079-155877--,00.html