In Michigan a lender may send a recovery agent to retrieve a vehicle that is in default of payment as soon as the default occurs (even one day late) unless the loan document states otherwise. However, the recovery agent is not allowed to breach the peace in the course of recovery. Breach of peace occurs when the recovery agent picks or opens a locked gate or garage. A recovery agent does not have the right to break into your garage to get your vehicle. You should contact the police to report the incident (especially since you do not know if this is the creditor or someone that stole your car) and you may want to contact an attorney to speak about repossession and the laws that govern these matters.
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