My son is a college student. His college lease increased in June. He said his new rent was $625. It turns out that it was $635. We sent a timely check for $625 each month. This week we discovered (by chance) that we were charged a $50 late fee each month - that is $150 for a $30 error. Is there a legal limit to the amount that can be charged as a late fee. If this was called interest, it would be a usurious rate.

