Mich. Comp. Laws § 500.6823
No company shall hereafter be organized under the provisions of this chapter for the purpose of insuring property other than that mentioned in section 6804. Any mutual insurance company whose business is limited by law or its charter to 1 or more counties, may provide in its charter or by amendment to its charter for insuring for its resident members any real or personal property owned by them and situated outside the county or counties in which the company is authorized to insure but in an adjoining county and may also provide for extending the insurance on personal property that may be temporarily absent not to exceed 6 months in a county adjoining a county or counties in which the company is authorized to do business, during which time the insurance on the personal property shall be in force as fixed in the company's charter or bylaws, so long as upon the adoption of any such article or amendment, the same shall automatically extend to all existing policies of the company, and that the insurance is subject to the same limitations as provided in section 6804.
MCL 500.6823