The short version: forget which tool is better. Work out which question you're asking, because the two tools answer different ones. Excel answers "what happened on the Henderson job." Power BI answers "which kinds of job keep making us money," automatically, every morning. Most NZ trade and services firms should keep Excel for the first and add Power BI only when someone actually asks the second kind of question monthly, and then licence two or three people, not the firm.
If the answer is Power BI, Power BI on Dataverse for a 10-person firm covers the NZ licence, who needs one, and the three reports to build first.
Getting Xero's numbers into either tool is its own small problem, covered in connecting Xero to Power BI.
The two questions, and why they need different tools
The spreadsheet you price and post-mortem a job in is genuinely the right tool: flexible, yours, and everyone reads it. Where it quietly fails is aggregation over time. The margin-by-month workbook gets rebuilt by hand, drifts from the source, and answers last quarter's question, and the point where a shared workbook or list stops coping has a close cousin in the SharePoint list limits post if that's your situation. Power BI's whole trade is the other direction: it connects to where job data already lives, Xero, the job tool, a Dataverse table, refreshes itself, and lets the pattern jump out: bathroom renos at 31% margin, insurance work at 9%, one client eating a day of unbilled admin a month.
What it costs, and the viewer trap
The licence numbers, checked August 2026: Power BI Pro at USD 14 a user a month, Premium Per User at USD 24, both since the April 2025 price rise, and Pro comes inside a Microsoft 365 E5 seat if you're already there. Convert at roughly NZ$1.72 plus GST and Pro lands near NZ$24 a person.
The catch that surprises small firms is that viewing generally costs too. A free-licence user can build reports for themselves, but to consume a report someone shares with you, you also need a paid seat, unless the content sits on dedicated Fabric capacity of F64 or larger, which is enterprise money no small firm spends for dashboards. So the "we'll buy one licence and share the dashboard" plan doesn't work. Licence the two or three people who build and read reports, the same discipline as the rest of the M365 stack: pay for the people who use the thing weekly.
The crossover test
| Signal | Stay in Excel | Power BI pays its way |
|---|---|---|
| The question | What did this job cost? | Which jobs, clients or months keep costing us? |
| The cadence | Once, at job end | Someone wants it monthly and current |
| The rebuild | Rare | Somebody hand-rebuilds a summary workbook every month |
| The sources | One sheet | Xero plus the job tool plus a spreadsheet, joined by copy-paste |
Two rows in the right column is the crossover. On one row, an hour of Excel each quarter still beats a licence and a data model. An AEC firm that would rather buy this reporting bundled than assemble it should still check what Total Synergy actually costs before committing to a practice-management platform instead.
The prerequisite nobody sells: Power BI can only report on data that exists somewhere structured. If job costs live in heads and dockets, fix the capture first. That's a job costing problem, and no reporting tool solves it.
Common questions
How much does Power BI cost per user?
As at August 2026, Power BI Pro lists at USD 14 a user a month and Premium Per User at USD 24, both up from the April 2025 price rise. Pro is also included in Microsoft 365 E5. The trap for small firms: viewers generally need a paid licence too, unless the content sits on Fabric F64-or-larger capacity, which no small firm buys for report viewing.
Should a trades business use Power BI or Excel for job costing?
Both, for different questions. Excel is the right tool for pricing one job and digging into what one job cost. Power BI pays for itself when you want the pattern across every job: which work types, clients or months keep making or losing money, refreshed automatically instead of rebuilt monthly by hand.
Do I need Power BI licences for everyone?
No, and this is the biggest saving. Licence the two or three people who build and read reports. Most firms need far fewer paid seats than they first assume; a licence for someone who might glance at a dashboard quarterly is money down the drain.
Get the reporting question sorted
If someone in your firm is rebuilding that monthly workbook by hand, book a free 30-minute call. Sometimes the answer is two Power BI seats and an afternoon of wiring; sometimes it's fixing the capture so any tool can report. Either way you stop paying a person to be a refresh button.