Zoho Creator and PayPal: I want to accept recurring and non-recurring payments

Hello,

I have been using the Zoho creator service to create forms for a non-profit site that will collect data and accept Paypal donations. We would like to have the option for those who donate to either donate once, or make recurring monthly donations.

Is there anyway to give the option? As far as I can tell, when setting up payment, the payment has to be either non-recurring or recurring, but there doesn't seem to be a way to give the customer filling out the form the option.

Am I approaching this the wrong way?

Thanks in advance for your input!