How do I determine if the event plugin is installed for my corrigo instance

Per this documentation I can see that it is possible to configure our corrigo installation for event push/web hooks.

How do I check if that plugin is already installed in my corrigo instance?

If/when it is installed where do I find the end point configuration for that plugin.

How can I get the cost associated with this plugin?

Would it be a problem for our external system to simply poll work orders for status changes every X minutes VS configuring the end point plugin? I realize this might not be the most efficient, but it might be an alternative if there is a cost associated with the plugin.

Thanks!