Every growing company eventually hits the spreadsheet ceiling: critical operations run on a maze of shared sheets, each a single point of failure with no audit trail and conflicting copies of the truth. Moving to an ERP is less a software project and more an operations redesign.
Build a custom system or configure an existing ERP?
Default to configuring an established platform (Odoo, ERPNext, Dynamics) before writing custom software. You inherit years of edge-case handling — tax rules, partial receipts, credit notes — that a bespoke build will rediscover painfully. Go custom only when the process is your genuine competitive advantage and no configuration can express it; even then, build around an extensible core rather than from scratch. The migration discipline in this playbook applies identically either way.
Whichever route you choose, define success numerically before the first import: invoice cycle time, month-end close duration, stock-count variance and hours of manual reconciliation per week. Those four numbers — measured before cutover and again thirty days after — are what turn 'the team seems happier' into a business case your CFO signs off on for phase two.
Why map the real process before writing code?
Spreadsheets encode years of undocumented business rules. Before building anything, sit with the people who use them and trace how data actually flows — including the exceptions everyone handles manually.
- Shadow every user for a day and record every manual workaround — each one is an unwritten requirement.
- Name a process owner per module; migrations stall when nobody can decide how invoicing really works.
- Freeze scope during discovery: new feature requests go on the roadmap, not into the migration.
Why migrate in slices instead of a big bang?
- Pick the highest-pain module first (often inventory or invoicing) and ship it end-to-end.
- Run the new system in parallel with the spreadsheet for one cycle to build trust.
- Only then migrate the next module — momentum compounds and risk stays contained.
Why does data cleaning take most of the project?
Years of inconsistent entry mean duplicate customers, mismatched units and orphaned references. Budget real time for a validated import pipeline with a dry-run mode and a clear error report — not a one-off script.
Users don't trust a system that loses their data once. Get the first import right and the rest of the rollout is a conversation, not a fight.
How do you bring the team along after cutover?
The system is live; adoption starts now. Run short role-based sessions (invoice clerks don't need inventory internals), keep a two-page cheat sheet per role instead of a 60-slide deck, and appoint one super-user per department as the first line of questions. Log every 'how do I…' question for the first month — recurring ones are missing features or missing training, and both are cheap to fix early. Track three adoption KPIs weekly: active users per role, tickets raised, and manual spreadsheet exports still happening. Most importantly, retire the legacy spreadsheets on an announced date. Parallel running forever means nobody ever trusts the ERP.
How do you keep operations running during cutover?
Pick a quiet business week, agree a freeze window for master-data changes, and script the rollback before you need it. Export the legacy sheet one final time, diff it against the imported ERP data with a reconciliation report (row counts, totals, control sums), and have the process owner sign off before switching users over. Parallel-running for one full cycle — invoices raised in both systems, compared line by line — is what turns nervous users into advocates.
Done well, the payoff is dramatic: one source of truth, real-time visibility, role-based access and audit trails — and hours of manual reconciliation handed back to the team every week.