Arachin 8 - Minimum and Maximum Amounts for Personal Valuations
One who vowed to give his own or someone else's symbolic value to the Temple pays according to the schedule given by the Torah , but if he is poor, a Kohen can reduce his payment. However, it is never less than a selah (shekel), since the Torah said, " And every valuation shall be in a sacred shekel ." Incidentally, it cannot exceed 50 shekels, the upper limit given by the Torah.
If one was poor, paid his selah, and then became rich, he does not have to pay the remainder, since he already fulfilled his obligation. However, if while being poor he paid less than a selah, it does not count, and now that he became rich, he has to pay the full amount.
On the subject of minimum and maximum, a woman who confused her menstrual cycle according to the Torah law, never has to compensate less than seven days and never more than seventeen. Due to the complexity of these laws, a custom arose to observe standard, although pretty long, separation time periods.
One who has spiritual leprosy - which was normally caused by defamatory comments - is confined for no less than a week but no more than three weeks.
Art: Louis Gallait - Monk Feeding the Poor