Conditional display of content…

I have a question that may not have a simple answer. I’ve searched through multiple forums, including here, and look through all potentially relative plugins (that I could find).

I’m using one of the PayPal plugins on a page (using shortcode), but I don’t want the PayPal plugin to display unless a checkbox has been checked. This is for a “Terms and Conditions” thing.

The plugin “If Shortcode” seems to come close to what I’m looking for, but I don’t know if it could be implemented this way.

Basically, I want to display a question and checkbox (this I can do), and on the condition the checkbox has been checked, then display the PayPal plugin using the shortcode.

Does anyone know of an easy way to implement this, either using a plugin or some trick I haven’t come across? Appreciate any help with this…