For manufactured or mobile homes, this form must be filed on or before December 31 of the year prior to the year for which the exemption is sought. The application filing period is from January 1st through December 31st.8 How do I apply for the homestead exemption? To apply, complete the application form DTE 105A, Homestead Exemption Application Form. To apply, a homestead exemption application (DTE 105A) must be filed with the Auditor after January 1 and on or before December 31 in the year of application. Show All Answers. 1. Who qualifies for the new Homestead Exemption? Applicants must own and occupy their home or mobile home or have ownership interest in it (i.e. Land contract), as of January 1 of the application year. The Homestead Exemption application can be filled out at the county auditor's office in which the property is located.