Hi David
1. Renewal and invoices and handled automatically by system, you don't have to do anything
2. For csv file monthly for distribution, Yes, I think you will have to export subscriptions data to an Excel/CSV file, then edit it yourself
3. I am not sure what's the best way to migration. You can prepare the data in a CSV file, then use Import features to import subscribers in the system
membershipprodoc.joomservices.com/subscr...t/import-subscribers
4. Actually, Membership Pro doesn't support tabs like in CB. Membership Pro only support basic custom fields types, no tab supported and honestly, for this feature, it is not power as CB
So I guess before going further, you should purchase a copy of Membership Pro, play with it to see whether it can be used to replace CB and CBSubs on your site. If it could not, we can refund your money
Regards,
Tuan