Most construction businesses hit the same wall around the £5–15m mark: projects are short, almost everything is subcontracted, and suddenly the amount of commercial admin looks like you should hire a commercial manager. But dropping £80–100k+ on someone to chase invoices, variations and retentions is a big call.
This page shows how to get the commercial discipline without the commercial-manager headcount – by moving the construction cost control rules into the system.
1. Why cost control actually breaks in subcontract-heavy construction
Your setup probably looks like this:
- 70–90% of project cost is subcontractor and supplier invoices.
- Projects are 6 weeks to 12 months, so even small admin delays make you lose visibility.
- You’re on Xero + spreadsheets (+ ApprovalMax) – which is great at accounting, not at enforcing project-level rules.
- You want invoices to land in the right project/cost code without changing how suppliers send them.
- You want retentions, variations and profitability in one view at CEO level.
When those things aren’t enforced by the system, they get enforced by… a person. That’s where companies think “we need a commercial manager.”
2. What a commercial manager in construction actually does (and why that matters here)
Why this section matters: this is what you’re paying £75–100k+ for. If you can see that 70–80% of it is rule-based, then it’s fair to say software can take that part.
2.1 The mission
A construction commercial manager’s job is (among others) to protect margin from tender to final account – by making sure everything is priced, instructed, tracked and reported.
2.2 Project-level responsibilities (the stuff your PMs do inconsistently)
- CVRs (Cost Value Reconciliation): every month, compare budget vs committed vs certified vs forecast to see if the job is still profitable.
- Variations/change control: log them, price them, make sure the client actually pays them.
- Subcontract orders: issue orders with the right retention, terms and value so you can control downstream payments.
- Valuations: line it all up so what you’re paying out matches what you’re billing.
- Contract admin: follow JCT/NEC so you don’t lose money on missed notices.
This is the exact thing that comes up on our customer calls – variations need to be tied to the client contract so profitability is real. Commitments (subcontracts, POs, etc) must warn us when they exceed the revised budget. That is textbook commercial-manager work, just made automatic.
2.3 Portfolio-level responsibilities (what a CEO actually wants)
- Monthly commercial report across all live projects
- Cash / WIP visibility (which jobs will need cash, which will release cash)
- Retention diary across projects
- Explaining margin movements to the MD/CEO
That’s the part the CEOs in UK construction usually mention in our calls: “show me retention across all projects with due dates and alerts,” not just per job.
2.4 Failure scenarios
Variation not captured
A PM or QS agrees to extra work on site, the subcontractor does it, but the variation never gets linked to the client contract in the system. All month your job looks perfectly profitable because the cost went up but the value didn’t. Then at final account the client says “we don’t have that instruction,” and you’re in a dispute you shouldn’t have had. A commercial manager would have logged that change on day one – your cost-control tool can force the same behaviour.
Order not linked to budget
Someone issues a quick PO for materials or a specialist sub, but they don’t tie it to the right cost code or revised budget. On paper the project still looks fine. At month-end, when invoices land, you suddenly see prelims or subcontract costs blown out and now you have to explain it to the board. A commercial manager would have checked the CVR and pushed back – a system can flag “this commitment will exceed the revised budget” at the moment the order is created.
Retention not diarised
You hold 5% on a subcontract, the job finishes, and everyone moves on. There’s no central diary to tell you “release retention in 6/12 months,” so the money just sits there. Multiply that by 10 jobs and you’ve got a big chunk of cash stuck for no good reason. A commercial manager or FD would have chased it – your system can show a portfolio-level “retentions due” list so no one has to remember.
These are all things a commercial manager would have spotted. Instead, what we’re saying is “let the system spot them.”
2.5 Cost
UK 2025 job ads for “commercial manager construction” are mostly sitting in the £57–78k salary band. By the time you add employer’s NI, pension, holidays and the general rise in labour costs, you’re realistically paying £75–100k all-in every year for that person.
Now compare that to what you actually said you want: monthly CVRs that don’t break, variations that can’t get lost, and a retention dashboard so cash doesn’t get stuck. That’s process work. It’s repeatable, it’s rules-based, and it happens every month.
A cost-control system can:
- run the same budget vs committed vs actual checks every single time,
- force variations to be tied to the client contract,
- keep a portfolio retention diary,
- push approved invoices to Xero,
…without taking holidays, getting sick, or needing 3 months to learn your way of doing CVRs.
So unless you genuinely need a senior commercial voice for negotiation and claims, it’s hard to justify £80k+ when a system can enforce 70–80% of the discipline for a fraction of that.
3. What a construction finance director / CFO does (and why it’s even pricier)
A construction FD has a different badge but part of the work overlaps.
What they care about:
- Cash-flow orchestration: pay subs weekly/monthly, get paid monthly/late.
- Job-costing accuracy: that what’s in accounting matches what projects committed and certified.
- Controls: invoices are approved, coded and auditable.
- Reporting to banks / external parties: they need clean, structured data.
- Choosing software so they don’t have to rebuild reports manually.
Cost: a finance director in the UK at this level is comfortably £120–170k salary, and with on-costs you’re looking at £150–220k.
Overlap with the commercial manager:
- both want structured invoices,
- both want commitments tied to budgets,
- both want retentions visible,
- both want monthly reporting.
This is the overlap we’ll automate.
4. The shared part we can automate instead of hiring
Let’s take the work both roles would do, and turn each into a “today → person → system” pattern.
4.1 Budgets → commitments with automatic warnings
- Today: PM creates a PO/subcontract in Excel or emails it; no one checks if the cost code has enough revised budget.
- What the commercial manager would do: open the CVR, compare committed vs budget, and tell the PM “you’re over on prelims/labour/material.”
- What the system does instead: when someone creates or approves that order, the tool checks the budget line and shows a warning / routes it for higher approval if it pushes you over.
This is the same safety net our calls keep mentioning again and again: “highlight warnings when committed costs exceed revised budget.”
4.2 Variations must be added to the client contract
- Today: variations are discussed on WhatsApp/email, priced in a separate sheet, and sometimes never make it to the client application.
- What the commercial manager would do: keep a change log, make sure every change is instructed, and add it to the next application so margin is real.
- What the system does instead: it forces each variation to be linked to the client contract or project so profitability, billing and reporting all see it.
This is exactly what our prospects keep asking for – variations shouldn’t be overlooked when billing the client.
4.3 Retention dashboard and alerts
- Today: each project has its own retention notes, and someone in finance/commercial updates a master sheet once a month (if at all).
- What the commercial manager / FD would do: maintain a retention diary, set reminders, and chase subs/clients as dates come up.
- What the system does instead: every order/payment carries retention % and due date; the dashboard rolls it up into “retentions due this month / next month” across all projects.
This is a pure CEO feature – one screen replaces a person remembering 20 dates.
4.4 Invoice inbox → classification → pushed to accounting
- Today: suppliers email invoices however they like; someone has to figure out which project/cost code it belongs to and make sure it’s approved before it hits Xero.
- What the commercial manager / FD would do: set up the process, chase missing approvals, make sure it’s coded right.
- What the system does instead: keeps the same supplier behaviour (email invoices), but inside the tool you attach them to the right project/order/cost code and then push to Xero approved.
4.5 Timesheets / prelim control
- Today: SLT “manipulates” data at month-end to make it reportable.
- What the commercial manager would do: compare prelim allowance vs actual labour/time spent.
- What the system does instead: creates work orders/time items and lets site teams submit time so the report is ready without SLT fixing it.
5. Construction cost control software checklist (CEO version)
5.1 Real-time budget vs committed vs actual
This is the backbone of automated CVR. You should be able to open a project (or even a single cost code) and immediately see:
- the original or revised budget,
- what’s already committed through orders, subcontracts or work orders,
- what’s actually hit the job through invoices or valuations.
If a tool can’t show those three numbers together, it can’t warn you about overspend and it can’t replace a commercial manager checking the CVR every month.
(See general construction cost-management principles from RICS here)
5.2 Subcontract / work order management
Most of your money goes to subcontractors, so the system has to create proper commitments the moment you award work. That means:
- issuing orders from inside the tool,
- setting retention on the order,
- tying the order back to the project budget and cost code,
- blocking or escalating when the order would push that code over budget.
That way commitments are created when decisions are made, not weeks later in Excel.
5.3 Variation / change-order control
Variations are where profit leaks. The software needs to:
- let PMs and site teams submit variations quickly,
- force each one to be attached to the client contract or project,
- roll approved variations into the next valuation or application.
That’s how you make sure extra work actually shows up in revenue, without relying on a commercial manager to police it.
5.4 Retention tracking (portfolio-level)
Seeing retention per project is useful; seeing it across all projects is what a CEO needs. Look for:
- retention percentage and release date on every contract or payment,
- a single retention report that shows “retentions due this month/quarter,”
- alerts for overdue retentions.
That turns “cash stuck in jobs” into “cash we know about and can chase.”
5.5 Timesheets / prelim control
Prelims are small but they drift fast on short projects. If the tool lets teams record time or work against predefined work orders, then those costs flow straight into the project reports. No more senior leaders “manipulating” data at month-end just to make it presentable.
5.6 Invoice intake + approval workflow
Suppliers shouldn’t have to change how they send invoices. The software should:
- receive invoices (email/inbox),
- let you match them to the right project, order or cost code,
- route them for approval,
- push them to Xero or your accounting system already coded.
That’s the piece a finance director or commercial manager would otherwise set up and chase.
5.7 Dashboards / KPIs
Finally, there has to be an owner-level view. At minimum:
- project profitability,
- overspend warnings,
- retentions due,
- variations pending or unapproved.
That’s the report you would have asked a commercial manager for every month—only now the system produces it.
(For wider best practices on construction cost management from RICS, see here)
6. CVR in construction: make it a system, not a person
A CVR (Cost Value Reconciliation) is just comparing what the job will cost vs what the job will earn at a point in time.
A simple CVR needs these fields:
- Budget / revised budget
- Committed cost
- Actual cost to date
- Value certified / application to client
- Forecast final cost
- Variance / margin
Most UK contractors do this monthly because invoices and applications are monthly. That’s why it often sits with the commercial manager/QS.
How to make CVR system-first:
- Start with the project budget in the tool (not in a private sheet).
- Create commitments from orders and work packages so you always know what’s been promised out.
- Match invoices/valuations to those commitments so actuals stay in step.
- Force variations to be linked to the client contract so value goes up when scope goes up.
- Let the tool calculate CVR (budget vs committed vs actual vs value) and show you margin movement.
- Export/share for the board without rebuilding in Excel.
This is the “monthly discipline” you’d otherwise be paying a commercial manager to maintain.
Conclusion
We started with a simple reality: you’re running a £5–15m construction business without a dedicated commercial manager, but the work on your desk – CVRs, variations, retentions, invoice approvals – looks like you should have one.
Then we unpacked what those people actually do. A commercial manager guards margin by keeping budgets, commitments, variations and valuations in sync. A construction FD makes sure the money side – cash, approvals, job costing, reporting – stays clean. Both are expensive, and both spend a big chunk of their time doing repeatable, rules-based work.
That’s the gap the software fills.
By making the system:
- create commitments from budgets,
- block or escalate overspend,
- force variations to attach to the client contract,
- keep a portfolio retention diary,
- and push approved, coded invoices to Xero,
…you get the same commercial discipline those roles would have brought, but without adding £75–200k to payroll.
So the takeaway of the whole article is: don’t scale headcount to get control – scale the rules. Put the rules in the tool so PMs, finance and you as CEO are all looking at the same, structured project data.
Then CVR just becomes the monthly snapshot of a process that’s already under control.
