Most businesses run invoicing and accounting in separate silos. One platform generates the invoice; another records it, matches payment, and files it to the ledger. The gap between them is where mistakes live. Invoice data drifts between platforms 5–10% of the time. A $5,000 invoice rounds to $4,998 in one system. A tax code is registered as 'GST' in invoicing but 'G' in accounting. A payment arrives; one platform marks it settled, the other still shows it pending. By year-end, your books don't reconcile, your accountant spends three days hunting discrepancies, and you can't trust your financial reports. Consolidating into a single platform— Orin's billing and accounting module , Xero, QuickBooks, or Wave—cuts that drift to under 1%. But only if you audit the right data before you migrate. Moving dirty data fast creates a bigger mess than leaving it split. Here are the nine data breaks that matter. 1. Invoice count and the historical orphan problem Start with the simplest audit: how many invoices do you have in your invoicing platform, and how many are recorded in your accounting software? Count invoices issued in your invoicing platform for the last three years. Then count invoices recorded in your accounting software for the same period. The difference is usually 3–7%. Where do the orphans come from? Draft invoices that were never sent or paid. Invoices sent but canceled after partial payment. Invoices recorded in accounting but never formally invoiced (manual journal entries, credit memos, adjustments). Invoices lost in a previous software migration or data export. Duplicate invoice numbers created by multiple users in different time zones. Before you consolidate, decide: do you migrate only paid invoices, or all invoices including drafts? Consolidating platforms assume invoices map 1:1 with accounting records. If they don't, your consolidated platform will either duplicate them or lose them entirely. 2. Invoice value precision and rounding drift Pull 50 random invoices from both platforms and compare the total amount. Invoice platform says $4,523.47. Accounting says $4,523.50. That's a 3¢ drift—rounding error. At scale, this kills reconciliation: Invoicing platform rounds to 2 decimals in one currency, then converts to another and rounds again. Net drift: 0.15%. Accounting software stores line-item amounts but displays totals as rounded. Export and re-import, and totals shift by fractions of a cent. Multi-currency invoices: platform A converts USD to SGD at 1.32, platform B uses 1.3201. Invoice worth $1,000 is $1,320 in one, $1,320.10 in the other. Before migrating, audit: does your consolidation platform round at line-item level or total level? Can it handle pre-rounding in the source data, or will it round again on import? If you're migrating 10,000 invoices and each rounds differently, you'll have 10,000 tiny reconciliation errors to chase. 3. Tax codes and jurisdiction mapping This is where most consolidations fail silently. Your invoicing platform labels tax as 'GST', 'SST', 'VAT', 'Tax Exempt'. Your accounting software calls them 'G1', 'S1', 'TX-0'. Before consolidation, you need a 1:1 map of every tax code used in invoicing to the corresponding code in accounting. Run this audit: Export your invoicing platform's list of all tax codes ever applied to an invoice. Export your accounting software's tax code list. Create a spreadsheet matching them. If you find orphan codes (used in invoicing but not in accounting, or vice versa), you've found a drift risk. For each code, verify the tax rate. Invoicing says 'GST 6%', accounting says 'GST 5%'? That's a mismatch waiting to break reconciliation. In Southeast Asia, this is especially critical. Malaysia uses SST, Singapore uses GST at 8%, Indonesia's PPN rate changed mid-year. If your invoicing platform applied the old 10% rate and your accounting software records the new 12%, consolidated data will show inconsistency. Auditors will flag it. 4. Customer tax IDs and validation gates If you sell to businesses (B2B), tax ID validation is where chaos breeds. Your invoicing platform might allow invoices with missing or malformed tax IDs. Your accounting software might require them. When you consolidate, the platform enforces stricter rules and rejects old invoices with bad IDs. Audit this before migration: How many invoices in your invoicing platform have blank tax ID fields? How many have IDs that don't match the format your accounting software expects? (E.g., an 8-digit ID when the format requires 10.) For invoices issued in Malaysia, do you have MyInvois-compliant tax IDs? FreshBooks and some other platforms don't enforce this; unified accounting systems will reject non-compliant ones on import. If 5% of your invoices have bad IDs, consolidation will stall on import. You'll have to manually fix them first—or accept that they won't migrate cleanly. 5. Payment method and reconciliation matching One of the biggest drift sources: payment matching. Invoice issued