Licence, implementation and first-year support together typically land between £500k and £3m+ for a mid-market organisation, depending on scope, customisation level and partner day rates. The implementation fee is usually 2–4× the annual licence cost. The number that surprises most CFOs is the internal cost: project management, business analyst time, UAT resource and the opportunity cost of pulling your best people out of BAU for 12–18 months. Budget for that too.

A focused, single-country F&O deployment typically takes 9–14 months from project kick-off to go-live. Multi-country or multi-entity programmes with complex integrations usually run 18–24 months. Anything shorter than 9 months for a meaningful scope should be treated with scepticism — the time is mostly consumed by data migration, UAT and change management, not configuration. Cutting those phases short is where programmes fail.

You will always use a partner — Microsoft does not deliver F&O implementations directly. The real question is which partner. Look for demonstrable F&O Finance and Supply Chain experience in your sector, a team that will actually be on-site (not a CV swap after the sale), and references you can call. Avoid partners who lead with their headcount rather than their delivery track record. Size of partner does not predict quality of delivery.

A single accountable executive sponsor, a steering committee that actually makes decisions, a design authority with real architects, a clear RACI, transparent risk and issue tracking, and a change control process that is respected rather than bypassed. Everything else flows from that.

Anchor the case in measurable outcomes: finance close speed, reporting accuracy, audit cost, retired legacy systems, reduced spreadsheet risk, process automation hours, and the cost of doing nothing. Be honest about implementation and run costs. A business case built only on "modern platform" language rarely survives contact with the CFO.