WeyantEnterprises
From the Invoice Settings page you could set an email address to get notifications to when paid online, i have mine setup with Pushover via email send.
Depending on your Email Config, you could have SMTP2GO CC you on all sends by address and define that address in the Mail From Configuration settings page.
It could be super beneficial to later have a 'email notify' setting in the Notifications settings page that would enable a checkmark and to enter an email address/SMS number for employee alerts, cc's, etc.