Because finance needs fields sales never filled in, so it opens a second list. Then an address is updated in one place and not the other, and an invoice goes to an office that closed last year.
A customer in Books is the record sales and support already use, with the billing side added: payment terms, tax registration, credit limit, billing address and everything ever invoiced.
There is one record. Finance-only fields sit on it under permissions, so sales can see the credit limit without editing it, and a change of address reaches the next invoice without being copied across.
A group buys through two trading names. Both are billing entities under one account, so statements go out separately while the credit limit and the aging view stay at group level.
It will not judge creditworthiness for you. It holds the limit and warns when an order would breach it; whether to ship anyway is a human call.
Flow owns the relationship and the agreed rates, Desk the support entitlement. Invoices, credit notes, receipts and the aging report all hang off this record.
Yes, and the invoice history moves with the merge. The retired record keeps a pointer so old links still resolve.
They warn by default. Set them to block at a threshold if you would rather stop the order than argue afterwards.
Yes — one organisation record holding both roles, which is what makes contra settlement possible.
Fourteen days, every module, no card. Or half an hour with someone who will run it on your own records and tell you where it does not help.