Switching from a toolbox of six or seven platforms to a unified system is not a weekend project. It's also not a six-month paralysis that eats through your contingency budget and leaves your team running two systems in parallel forever. The sweet spot is 90 days: a realistic, phase-gated plan that lets you migrate data, train people, and cut over live without a customer-facing outage or your operations team sleeping in the office. This is the playbook we've seen work repeatedly, whether you're moving from Slack + HubSpot + Stripe + Zapier to a unified platform, or consolidating legacy spreadsheets and point tools. The structure is the same: weeks 1–4 audit and prepare, weeks 5–8 test in parallel, weeks 9–12 go live and support . Done right, your customers never notice the switch. Weeks 1–4: Audit, map, and train Most implementation failures start with data blindness. You think you know what's in your CRM, your billing system, your email, your customer portal. You don't. Week one is archaeology. Week 1: Data inventory and quality check Export everything from every tool. CRM contacts and deals, past invoices, contracts, customer interaction logs, team members, permissions. Export it all to CSV. Don't make assumptions. Count and categorize. How many contacts? How many active deals? How many invoices per month? How many overdue payments? How many contracts are unsigned? This number is your baseline for testing cutover later. Identify duplicates. You almost certainly have the same contact in your CRM three times. Same invoice number issued twice. Same customer in two deal pipelines. Flag them now; they will cause reconciliation hell in week 11 if you don't. Document field mapping. Your old CRM's 'Account Owner' might map to the new platform's 'Primary Sales Rep.' Your old invoicing tool's 'Payment Term Days' might become 'Net 30' as a dropdown. Write these down in a spreadsheet. This is your transformation logic. Weeks 2–3: Build your data migration playbook Clean as you go. Don't plan to 'clean the data later.' It doesn't happen. If a contact has no email and no phone, decide now: does it move into the new system, or do you archive it? If a deal is 'stuck' in your pipeline for 18 months, is it a real deal or should you close it as lost? Make the call in week 2 while you still have time to validate your logic against a sample of live data. Test the migration tool or API. If you're using Orin's CRM or another platform with a built-in importer, run a test migration on a sandbox environment this week. Does it handle your date formats? Does it respect your custom fields? Do your invoice numbers stay intact? Find the gaps now, not on cutover day. Create your master record definition. What is the single source of truth for a customer record? Is it the CRM, the accounting system, or a hybrid? Define it. If your old CRM says a customer's name is 'ACME Corp' and your invoicing says 'Acme Corporation', which one wins in the new system? Decide once; apply everywhere. Weeks 3–4: Train and assign roles Run hands-on training by function. Your sales team doesn't need to understand invoicing flow; your ops team doesn't need to master the AI chat widget . Segment training by role. Show each team the 5–7 workflows they actually use. Designate power users. Pick 2–3 people per function who will be your 'go-to' in week 5 when real questions arise. They should already have platform access and should be comfortable breaking things in a sandbox. Document the gotchas. What will feel different? If your old CRM auto-populated a field and the new one doesn't, tell people now. If unified messaging will change how they receive customer emails and WhatsApp messages, walk them through it in week 3, not week 9 when they're live. Weeks 5–8: Parallel run and breakage testing Week 5 arrives and everyone is nervous. This is when you prove the system works by running it alongside your old tools. No switching over yet. Just data flowing two directions. Weeks 5–6: Populate the new platform and test data integrity Run your first full migration. Load all historical data into the new platform. Invoices, contacts, deals, contracts—everything. Then immediately audit it. Spot-check 10 customer records end-to-end. Pick 10 real customers at random. Verify that their contact record, their open invoices, their deal history, and any contracts are all present and correct. If something is wrong, fix the migration logic and re-run. Reconcile totals. If your old system shows 2,847 contacts, the new one must show 2,847 (or a clearly documented reason for fewer, like duplicates you merged). If your old invoicing system shows $340k in unpaid invoices, the new one must show the same. These numbers are your canaries. If they diverge, stop and investigate. Weeks 6–7: Shadow mode—live transactions, dual recording New transactions go into both systems. When your sales team closes a deal this week, they close it in the old CRM and the new one. When you send an invoice, you s