Marking Customers as overdue

I would like to be able to mark clients as over due or no work until they are paid up. Is there a way to do this so that we can’t make tickets for them or that there is a error message that client is overdue and that we won’t preform any work till they are paid?

I don’t think there’s any great way to do this, but one hack I remember seeing people do was add a Customer Custom Field of the popup type, then whenever the custom page is opened it pops up. You can also rename the customer to have some sort of tag or an emoticon. Might be problematic if that gets into communications though. I think there was some other way to tag without renaming but I forget how people did it, maybe someone else will chime in.

Edit customer and enable “INTERNAL TICKET WARNING USAGE”.
Customer custom field type of Popup.

I believe those are you 2 options.

Thank you! This looks this will work.