Responsibility across several accounts.
DECIDE YOUR POSITION
You take backups and can restore on request. Most valuable, most work, worth charging for. Clients take their own. Lowest effort, and say so clearly in writing. Both, which is the honest recommendation.
WHAT TO PUT IN WRITING
How often backups run How long they are kept How to request a restore Whether it costs anything How quickly it can be done
The ambiguity here is what causes disputes on the worst day of the relationship.
PRACTICALLY
Configure per-account backups sending off the server Keep a monthly copy for each client Test a restore on one client site quarterly Keep a list of which client has what
WHAT NOT TO DO
Imply comprehensive backups you are not taking. That promise surfaces when a client has lost everything.
RESELLER ACCOUNTS
Server-level backups within your plan cover accounts inside it. Check retention, and supplement with your own.
CHARGING FOR IT
Managed backups with a guaranteed restore is a service worth paying for. Price it.
