Inventory the real system
List installed modules, custom code, scheduled jobs, reports, integrations and external dependencies.
Profile and reconcile data
Identify duplicates, incomplete masters and accounting or inventory balances that must reconcile after conversion.
Rehearse the conversion
Run the migration in a sandbox, record timings and repeat until the process and rollback window are understood.
Validate business continuity
Have process owners test critical flows with representative data before approving production cutover.
Practical next step
Validate the decision against your own processes, data, controls and operating model before committing to implementation.