Ability to add a 1 time registration fee for drop in classes.

I think it would be beneficial to be able to apply a registration fee to any students enrolling for drop in classes. This registration fee would be a 1 time fee per season that the class is assigned to. I feel like adding a registration fee to these classes concretes the students commitment level. Right now we run into issues where a student is signing up for a drop in class/date and since there is no fee attached to the commitment, we are always unsure how many students to plan for the class each week. Thank you!