Modifying site groups
At all sites and entities, set up Site Groups for the various sites that will be doing centralized order entry, transfer orders, or financial reporting.
Since Site Groups are replicated (in the Site Admin category), they can be set in one site or entity and be replicated to other linked sites/entities.
One or more site groups were set up when you added sites, but the sites in the groups might need tweaking, or you might want to define additional groups for additional purposes.