I agree with Mr. Weinman. The lease should give you the answer. If it is not clear from the lease, then I would argue that he is not entitled to late fees upon late fees. You might also have an argument that the charges are usurious. You might not win on that, but there is a criminal usury statute in Michigan. If that applies, the landlord could be looking at jail time and a huge fine. If I was your landlord, I would not want to test that statute.
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