Are you wanting a customized "donation"-type fee where customers enter their own amount? If so, follow these steps.
Step 1 - Head over to the My Company > Items tab.
Step 2 - Click the blue plus in the top right next to the Charge Items.
Step 3 - Name the Charge Item
Step 4 - Choose the following options in the settings:
Type: Standard fee
Required: Optional at enrollment or in a payment plan
Quantity: When purchasing this item, quantity can be specified
This setting allows you to set a price per unit, and allows the Enrollee to enter the desired quantity at enrollment. The total due is calculated for them.
Payment Plans: Enabled for Payment Plans (if you need to add it to one or more payment plans) or Due at enrollment (if it's only due at enrollment and NOT on a payment plan).
Prepayment: No
Click "Save." Now you can add the custom charge item to Program or Class pricing.
Add to Pricing
Follow these steps to add the new custom Charge Item to a Program or Class.
Step 1 - Add the Charge Item. Under Pricing (either on the Program or Class), add the new Charge Item under the total cost (after selecting "Fixed Cost").
Step 2 - Add Amount. Once you add the Charge Item, you will have to add an amount. We recommend "$1.00" so that customers can donate in any amount.
NOTE: You CANNOT add a zero ("0") in the dollar amount field or the Charge Item will not show up on the Enroll Form. Enter an amount such as "$1.00"
Step 3 - Move Fee to "Due at Enrollment" Section. If you are using Payment Plans and want to have the donation item in them, you will need to change the setting to "Manually set pricing for [#] payment events," then add the donation Charge Item under the "Due at Enrollment" section. Change the amount back to $1 (or whatever amount you set it to). Click "Apply" to save any changes.
Step 4 - Save. Select "Save" to save the changes made to the Program or Class.
Step 5 - Test. To be sure the pricing is set up correctly, go through the enroll form (click "Enroll" on the left menu to go through it as an admin user who is able to skip over required fields; or use the enroll link and enroll in an incognito/private browser window as a customer).
Here is an example of how this might look on the Enroll Form:

