Charge 2 form that has multiple one of plan amounts?
check out the docs here - http://squarebit.co.uk/software/craft/charge/usage/reference/payment-options and note this bit:


  planIntervalCount accepts int The number of periods for a recurring
  plan. If you're creating recurring charge, this is required, and must
  be 1 or higher. Not including, or passing a 0 value will create a
  one-time charge.


So, you could do

&lt;input type="hidden" name="planIntervalCount" id="planIntervalCount" value="0"/&gt;


for a one off payment.