Brainless Technologies Ltd.

Hey, thinking of getting this panel, but does it have support for any billing features, ie. paypal, to help automate the setup of new servers, send invoices, and stop servers of those who are not paying?

There is currently no support for integrated billing. You can set a disable date for servers.

If you're still interested let me know.

Is there any way to automate setting up and setting server expiry dates? If so, I can probably grab some open-source billing system and try to set it up to integrate with UGCC.

Yes, you should be able to use the panel's API and direct access to the panel's database to accomplish what you need.