Notify client prior to deletion due to inactivity
Based on this thread, https://requests.whmcs.com/topic/backup-user-data-before-data-retention-deletion I'd agree that a client deletion means client deletion and that I have no right to their data when they request deletion, but it seems perfectly reasonable to ENSURE that the client wants to be deleted if the process is automated. I have a handful of clients who don't have any services, they simply want the occasional convenience of credit card billing. Technically, they're inactive, have no products and would fall into that automated deletion category.
I have been sent emails from other companies saying "you haven't logged in in a while - you will be deleted unless you intervene" or some such language. If a client is flagged for deletion, at the very least, the client needs to be informed and given a chance to opt back in. Surely this kind of email/procedure can be triggered without too much fuss.