When I have a multiple choice listing (ie. $50, $75, $100), once a person selects, they are unable to "unselect". For example, if they change their mind about taking a class with that cost associated. How I can add the unselect, without having to add an "other" option?
You can try Chcck box or Multiple choices fields. These will allow you to unselect the field. If you must use the Single choice field (the radio buttons) you may want to add a choice "None" for the user to choose.