Build the posting crosswalk that turns Business One's determination hierarchy — account setup, business-partner control accounts, item, item-group and warehouse rules, tax codes, distribution rules and projects — into D365 posting profiles, inventory posting and tax configuration.
If the chart of accounts is the first design gate, the posting crosswalk is the second — and it is the one that decides whether the first close after go-live is calm or forensic.
Account selection in Business One is a hierarchy, and the hierarchy is what makes decomposition necessary rather than optional.
The source package identifies ten posting mechanisms that any Business One programme must resolve. Confidence is high on most and medium on three — sales revenue determination, landed cost, and production — and the medium ratings are stated rather than smoothed over.
Distribution rules and project codes influence dimensions, not account selection, once the target design is in place. That distinction is worth stating explicitly in the crosswalk, because source practice blurs it: a distribution rule can feel like part of "where the posting goes" when it is really part of "what the posting is tagged…
Select representative documents per company database — each sales document path in use, goods receipt with and without a subsequent invoice, price-variance cases, transfers, adjustments and counts, landed-cost documents, production receipts if in scope, settlements with and without discount, and a foreign-currency example of each.
The posting crosswalk pulls one determination hierarchy apart and re-homes it across several target structures.