Operations
Materials, labour and overhead, and the three places the number usually goes wrong. If labour is booked separately from the product, your product cost is not your product cost.
Retail generates hundreds of small transactions and one daily question: does the cash in the drawer match the sales in the system? Here is what has to be true for the answer to be yes.
Guides
What to bring, what to leave behind, and why opening balances matter more than history. A migration plan that fits on one page.
Accounting
A long close is rarely a staffing problem. It is a list of things that were allowed to go unresolved during the month, collected and resolved at the end of it.
The hardest part of a second branch is not the stock. It is that every record now needs to know where it belongs, and the ones that do not know become invisible.
If you cannot explain how an item cost was calculated, you cannot defend the margin that depends on it. What moving average actually does, and where it goes wrong.
Two numbers that must match and usually do not. The causes are few and specific, and each one points at a different missing control.
Choosing a system
Spreadsheets do not fail loudly. They keep producing a number long after it stopped being the right one. These are the symptoms worth noticing before an audit notices them for you.