How to use configurable list widget to perform calculations for payment

Hi,

Unfortunately you can't use configurable list widget to perform calculations. You will have to use some other form tool to make your calculations. 

You can use conditions with combination of radio buttons and textfields with conditions.

Folllow these guides i provided to achieve your goal

 http://www.jotform.com/help/57-Smart-Forms-Using-Conditional-Logic

http://www.jotform.com/help/268-How-to-Insert-Text-or-Mathematical-Calculation-into-a-field-using-a-Condition

http://www.jotform.com/help/196-Hide-or-Show-Multiple-Fields-at-Once

Please let me know if i can be of more assistance to you.

Best regards.