Quick Answer
BigChange captures job time, materials, and vehicle data in one platform. Xero handles invoicing and accounts. Make.com sits between them, syncing completed jobs to Xero invoices in real time and flagging any job where costs look wrong. The result: you see true profit per job, per van, per engineer, without anyone typing a number twice. Setup takes a weekend. Running cost is around £110 per user per month for the full stack.
Table of Contents
- Why most fleet businesses are guessing at job costs
- What BigChange actually does
- How the BigChange to Xero data pipeline works
- Where Make.com fits in
- Setting up the integration step by step
- Cost anomaly detection with Make.com AI modules
- What this stack costs per month
- BigChange vs alternatives for fleet job costing
- What tradespeople are saying
- Recommended videos
- Frequently asked questions
- My verdict
BigChange
Xero
Make.comWhy most fleet businesses are guessing at job costs
Most trades businesses with a fleet think they know what each job costs. They add up materials, estimate the labour hours, maybe account for fuel. Then they invoice and move on. The problem is that the real cost often sits 12 to 18 percent higher than what they estimated, and they only find out at the end of the quarter when the accountant flags thinning margins.
The gap comes from all the stuff nobody tracks in real time. Drive time between jobs. Idle time on site. Materials pulled from the van but never logged. Return visits that get absorbed into the next job's schedule. Fuel costs that get lumped into one monthly figure instead of allocated per job.
For a business running 10 or more vans, that 12 to 18 percent gap adds up fast. On a £500,000 annual turnover, you could be losing £60,000 to £90,000 in untracked costs. That is not a rounding error. That is a full-time salary disappearing into the space between your spreadsheet and reality.
A facilities management company running 15 vans at an average of 4 jobs per day generates 300 job cost records per week. If each one is off by even £15, that is £4,500 per week in invisible margin erosion, or £234,000 per year.
The fix is not more spreadsheets. It is connecting the systems that already hold the data, so cost information flows from the field to the accounts automatically. That is what this BigChange, Xero and Make.com stack does.
What BigChange actually does
BigChange is a 5-in-1 job management platform built in Leeds. It combines CRM, job scheduling, live vehicle tracking, a mobile workforce app, and financial management into a single system. Over 2,000 UK businesses and nearly 100,000 users run on it.
The key thing for job costing is that BigChange already captures the data you need. Every job card records start time, end time, materials used, photos taken, customer signatures, and engineer notes. The GPS tracking logs every journey, every stop, every minute of idle time. The scheduling system knows which engineer was assigned, how long the drive took, and whether the job ran over.
All of that sits in one database. No exporting CSVs from three different systems and pasting them into a master spreadsheet. The vehicle tracking is baked in, not bolted on. When your engineer starts driving to a job, BigChange knows. When they arrive, it logs the time. When they mark the job complete and the customer signs off, the whole cost picture is right there.
CRM for customer records and history. Job scheduling with route optimisation. Live GPS vehicle tracking with driver behaviour monitoring. Mobile app for paperless job sheets, photos, and signatures. Financial management for quotes, invoices, and purchase orders. All of it runs through one login.
BigChange reports that customers save £5 for every £1 spent on the platform, with an average 9.2 percent shorter job duration and 85 percent reduction in paperwork. Those numbers will vary by business, but the direction is clear: fewer manual steps means fewer gaps where costs go untracked.
How the BigChange to Xero data pipeline works
BigChange has a native Xero integration. Once connected, completed jobs flow from BigChange into Xero as invoices without anyone retyping the details. Contacts sync between the two systems, and payment status updates flow back from Xero to BigChange so your operations team can see who has paid without opening a separate app.
The native integration covers the basics well. When you raise an invoice in BigChange, it pushes to Xero automatically and gets flagged. You can choose which direction contacts sync, so if Xero is your master record for customer data, BigChange pulls from there rather than duplicating work.
But here is where it gets limited. The native integration handles invoices and contacts. It does not push granular job cost data into Xero's tracking categories. It does not alert you when a job's actual costs exceed the estimate by more than 10 percent. It does not build a real-time margin dashboard. For that, you need the automation layer.
This is the gap Make.com fills. It connects to both BigChange (via the REST API) and Xero (via Make.com's native Xero module), and it can do things the native integration cannot. It can watch for completed jobs, pull the full cost breakdown, calculate the margin, push structured data into Xero tracking categories, and fire off alerts when something looks wrong.
Where Make.com fits in
Make.com is a visual automation platform. You build workflows, called scenarios, by connecting modules from different apps. It has a native Xero module with full read and write access to invoices, contacts, bills, and tracking categories. For BigChange, you use the HTTP module to connect via BigChange's REST API.
The setup works like this. A Make.com scenario runs on a schedule, say every 15 minutes. It calls the BigChange API to pull all jobs completed since the last check. For each job, it extracts the labour hours, material costs, travel time, and fuel allocation. It then pushes that data into Xero as a categorised bill or journal entry, tagged with tracking categories so you can run profit and loss reports per job type, per engineer, or per region.
What makes this more powerful than the native integration is the logic layer. Make.com lets you add conditional steps. If the job cost exceeds the quote by more than 15 percent, send a Slack notification to the operations manager. If fuel costs per job spike above the 90-day average, flag it for review. If a specific engineer consistently runs 20 percent over on labour hours, generate a weekly summary for the team lead.
Trigger: scheduled every 15 minutes. Step 1: HTTP call to BigChange API for completed jobs. Step 2: iterator to process each job. Step 3: router with three paths: (a) push to Xero with tracking categories, (b) check margin thresholds and alert if breached, (c) log to Google Sheets for dashboard reporting.
Make.com's Pro plan starts at around £18 per month and gives you 10,000 operations, which is more than enough for a fleet of 10 to 30 vehicles processing 20 to 60 jobs per day. The visual builder means you do not need a developer to set it up, though having someone comfortable with REST APIs helps for the BigChange connection.
Setting up the integration step by step
This is not a weekend project if you have never touched an API before. But if you have set up a Zapier zap or built a simple Make.com scenario, you can get this running in a day. Here is the process, stripped to the essential steps.
Step 1: Get your BigChange API credentials. Log into BigChange, go to Settings, then API. Generate an API key and note down your account endpoint. BigChange uses a REST API with JSON responses, so Make.com's HTTP module handles it natively.
Step 2: Connect Xero to Make.com. In Make.com, add a Xero module to any scenario. It will redirect you to Xero's OAuth page where you grant access. This takes about two minutes. Once connected, Make.com can read and write invoices, contacts, bills, and tracking categories in your Xero account.
Step 3: Set up Xero tracking categories. In Xero, go to Settings, then Tracking. Create two tracking categories: one for Job Type (reactive, planned maintenance, installation, inspection) and one for Engineer or Region. Every cost that Make.com pushes in will be tagged with both, giving you granular P&L reporting.
Step 4: Build the Make.com scenario. Create a new scenario with a scheduled trigger. Add an HTTP module to call the BigChange API endpoint for completed jobs. Parse the JSON response. Add a Xero module to create or update invoices with tracking categories attached. Add a filter module for margin threshold alerts.
Step 5: Test with a small batch. Run the scenario manually with 5 to 10 recent jobs. Check that the data appears correctly in Xero with the right tracking categories. Verify the margin calculations match what you would calculate manually. Fix any mapping issues before turning on the schedule.
Step 6: Go live. Set the scenario to run every 15 minutes. Monitor it for the first week, checking that jobs flow through without errors and that Xero reconciliation still works cleanly.
BigChange's API has rate limits. If you run 30 or more vans, space your calls or use pagination to avoid hitting the cap. Make.com's built-in retry logic handles occasional 429 errors, but designing your scenario to batch requests is cleaner than relying on retries.
Cost anomaly detection with Make.com AI modules
This is where the stack goes from useful to properly valuable. Make.com now includes AI modules that can analyse data mid-scenario. You can route job cost data through a GPT-5 or Claude module that compares each job against historical averages and flags outliers.
The practical application for fleet job costing is straightforward. You feed each completed job's cost breakdown, including labour, materials, fuel and travel, into an AI module with a prompt like: "Compare this job's costs against the 90-day average for this job type. Flag anything more than 15 percent above average. Suggest possible reasons."
The AI module returns a structured response that Make.com routes to a Slack channel or email alert. Your operations manager gets a message saying something like: "Job 4872 at 14 Elm Street cost £340 against a 90-day average of £210 for reactive boiler repairs. Labour was 4.5 hours versus a 2.8-hour average. Materials were standard. Possible cause: return visit or complex fault."
If catching cost overruns on just 5 jobs per week saves an average of £80 each, that is £400 per week or £20,800 per year. The Make.com Pro plan that runs the detection costs around £18 per month. The AI module calls add perhaps £10 per month. The payback period is measured in days, not months.
You can also use the AI modules for margin alerting. Set up a scenario that runs nightly, pulls all jobs completed that day, calculates gross margin per job, and sends a summary to the business owner. Jobs below your target margin get highlighted. Over time, you start to see patterns: certain job types that consistently underperform, certain routes that cost more in fuel than you priced for, certain engineers who are slower but produce fewer callbacks.
What this stack costs per month
Pricing clarity matters. Too many integration guides wave their hands at costs. Here are the real numbers for a 10-van fleet operation.
| Component | Plan | Monthly cost | Notes |
|---|---|---|---|
| BigChange Plus | Plus (per user) | £99.95 per user | Includes GPS tracking, scheduling, mobile app, CRM, financial tools |
| Xero | Standard | £28 | Unlimited invoices, bank reconciliation, VAT returns, tracking categories |
| Make.com | Pro | ~£18 | 10,000 operations per month, 1-minute scheduling, error handling |
| AI module costs | Pay-per-use | ~£10 | GPT-5 or Claude API calls for anomaly detection, varies with volume |
| Total (10 users) | ~£1,056 | £999.50 BigChange + £28 Xero + £18 Make.com + £10 AI |
That is roughly £106 per user per month for the full stack. BigChange is the largest line item, but it replaces standalone vehicle tracking (£15 to £25 per vehicle per month), separate scheduling software (£30 to £50 per month), and paper job sheets. When you factor in the tools it replaces, the net new cost is often lower than people expect.
For a smaller operation running 5 vans, you could start with BigChange Standard at £79.95 per user and Xero Starter at £14 per month. Make.com's free plan gives you 1,000 operations per month, which covers about 30 jobs per day on a 15-minute sync cycle. Total: around £414 per month for 5 users, or £83 per user.
BigChange vs alternatives for fleet job costing
BigChange is not the only platform that can do this. Here is how it stacks up against other options for fleet-based job costing with Xero integration.
| Feature | BigChange | Simpro | Commusoft | Tradify |
|---|---|---|---|---|
| Built-in GPS tracking | ✓ | ✗ | ✗ | ✗ |
| Native Xero integration | ✓ | ✓ | ✗ | ✓ |
| REST API for automation | ✓ | ✓ | ✓ | ✓ |
| Job costing built in | ✓ | ✓ | ✓ | ✓ |
| Driver behaviour monitoring | ✓ | ✗ | ✗ | ✗ |
| Geofencing | ✓ | ✗ | ✗ | ✗ |
| Mobile app | ✓ | ✓ | ✓ | ✓ |
| UK-based support | ✓ | ✓ | ✓ | ✗ |
| Starting price (per user/mo) | £79.95 | Quote-based | Quote-based | ~£30 |
BigChange's main advantage for fleet job costing is the built-in GPS tracking. Simpro, Commusoft, and Tradify all require a separate vehicle tracking subscription and a way to merge that data with job records. BigChange does it in one system, which means Make.com only needs to connect two platforms (BigChange and Xero) instead of three.
The trade-off is price. BigChange starts at £79.95 per user per month, which is quite a bit higher than Tradify at around £30. For a sole trader or two-person operation, BigChange is overkill. It is built for businesses running 10 or more engineers where the fleet tracking and scheduling optimisation justify the cost. If you run fewer than 5 vans, Tradify with Xero and Stripe is the lighter option.
Commusoft users looking for similar job costing automation should check our guide to Commusoft, Sage and n8n for automated P&L dashboards, which covers a similar pattern with different tools.
What tradespeople are saying
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Frequently asked questions
No. BigChange has a REST API, and you connect to it using Make.com's HTTP module. You set up the API endpoint, add your authentication header, and Make.com handles the requests. It takes about 10 minutes to configure if you have your API key ready.
You can, but Make.com is better for this use case. The visual scenario builder handles the branching logic (margin checks, anomaly alerts, conditional routing) more naturally than Zapier's linear zap structure. Make.com is also much cheaper for high-volume API workflows.
BigChange also integrates natively with Sage. Make.com has Sage modules too. The same pattern works: BigChange for data capture, Sage for accounting, Make.com for the intelligence layer. The setup is nearly identical.
BigChange's GPS tracking gives you exact mileage per journey. You multiply by your average pence-per-mile fuel cost (most fleets sit between 15p and 25p depending on vehicle type) and allocate that to the job. It is not perfectly precise because it uses distance rather than actual fuel consumed, but it is far more accurate than guessing or splitting your monthly fuel bill evenly across jobs.
Honestly, no. At £79.95 per month minimum, it is priced for businesses with 10 or more engineers where the fleet tracking and scheduling features justify the cost. If you are a one-person operation, look at Tradify with Xero instead.
BigChange onboarding typically takes 2 to 4 weeks including hardware installation in vehicles. The Xero connection takes minutes. The Make.com automation layer takes a day to build and test if you know what you are doing. Budget a month from decision to fully operational.
My verdict
If you run 10 or more vans and you are still doing job costing in spreadsheets, you are almost certainly leaving money on the table. BigChange gives you the data capture. Xero gives you the accounting. Make.com gives you the intelligence layer that connects the two and spots problems before they eat your margins. The setup is not trivial, but the payoff is real: you stop guessing what each job actually cost and start knowing. For fleet operators doing facilities management, planned maintenance, or multi-site reactive work, this is the stack I would build on. For smaller operations, the same principle applies but with lighter tools. You can read about Make.com automations for lead response or the Payaca and Xero pipeline for renewables for alternative integration patterns.
