The implementation covered everything except the reconciliation that actually hurts
Posting groups, dimensions, VAT, the item card: all designed properly. Then the first Adyen payout arrives, covering three hundred orders in one net amount, and somebody opens Excel. Six weeks later the unapplied entries are four figures and nobody is sure which are real.
Free to start with nothing installed, no partner hours, and nothing to design during hypercare.
Why this gap exists in almost every e-commerce implementation
Three reasons, none of them anybody's mistake.
Business Central assumes one customer pays one invoice
Which is true for wholesale and almost never true online. A payout is one net amount covering hundreds of orders, minus fees, minus returns, with a reference that belongs to the provider rather than to your invoice series.
The demo used clean data
In the demo the reference matched. In your files it is SO12356-1 against invoice 12356, and one character of difference is the whole reason a person is now doing this by hand.
Nobody owned the decisions
Which account fees go to, what counts as a rounding difference, what to do with a payment 7,56 short. Small policy calls that were never made, so they get made again every day, slightly differently.
A clean AR ledger by Friday, without opening a support ticket
Safe to add during hypercare
Questions from new BC teams
We are still in hypercare. Is it too early?
No, and earlier is usually better. No matching logic goes into Business Central, so it cannot interfere with anything being stabilised, and a clean AR ledger makes every other issue easier to see.
Do we need the API connection to Business Central?
Not to start. An open items export works fine on day one, and you can connect properly later when IT has time.
Our chart of accounts is not finished.
Fine. Account numbers sit in the rules and are edited in one place, so changing 6570 later takes seconds rather than a reimplementation.
Should our partner set this up?
They can, but the person who does the reconciliation is the better choice. The decisions are accounting policy rather than configuration, and they are the one who knows the answers.
We post one revenue journal a month from payout reports. Does this help?
Probably not. Kvitta works against open customer ledger entries, so without receivables per order there is nothing to match.