Managing Trade Business Inventory — How to Stop Wasting Money on Materials You Can't Find

I've walked into more vans and workshops than I can count where the owner swears blind they'll never buy another box of 25mm conduit saddles — only to find a half-empty box of the exact same ones buried under three generations of offcuts, empty cable drums, and a 2019 newspaper they keep meaning to recycle.

Every tradie does it. You're at the wholesaler counter at 7am, you know you've got a box of 6mm TPS somewhere, but you can't find it, the job's waiting, and the sparky on site is calling. So you buy another one. That's $30 you didn't need to spend — and it happens once a week, fifty-two weeks a year. That's fifteen hundred bucks of margin you're just handing over because you can't find your own gear.

Inventory management for a tradie isn't about a warehouse with barcode scanners and a forklift. It's about knowing what you've got before you buy it again, and tracking what you use so you can price the next job properly.

The problem is simple: we buy materials job-by-job, but we don't clear leftover stock back into a system. That $80 roll of 10mm earth cable left over from last week's house rewire goes in the van — and it sits there until someone buys another one because nobody remembered it was there.

The second problem is worse. You quote a job based on supplier prices from last month. You buy the materials at today's prices — which are higher. You install them, invoice the job, and the margin you quoted is gone because copper went up 12% while you were waiting for the client to sign. If you're not tracking actual material costs against your quote, you're flying blind on every job.

The third problem is the one nobody talks about: dead stock. The specialist tapware you bought for a bathroom renovation that got cancelled. The weird-sized ducting you ordered for a commercial job that changed scope. The paint colour the client chose and then changed their mind on. That stuff sits in the back of the shed, depreciating by the day, until you either dump it at a loss or lie awake at 2am wondering why your bank balance doesn't match your revenue.

You don't need QuickBooks for this. You need a process that takes thirty seconds and a piece of software that makes it easy to track what went where.

Here's the simple version. For every job, list the materials you bought and what they cost. When the job's done, log what you actually used — not what the invoice said you ordered. The difference is your leftovers. Now you've got a running list of: this roll of cable is on the shelf, this box of fittings is in the van, this duct is in the shed. Next time you quote a job that needs any of it, you check the list first. You don't buy what you already own.

This is the kind of thing Trade Track makes dead simple — every job tracks its materials, you can see what's allocated and what's been used, and the leftovers are flagged before you go back to the counter. It's not a warehouse management system. It's a "stop buying the same box of saddles twice" system.

If you track nothing else, track your material variance. That's the difference between what you allowed for in your quote and what you actually spent. If you're consistently over by 10% on materials, you're pricing every job wrong. If you're consistently under, you're either overpadding your quotes (and losing work) or you've got a blind spot in your takeoffs.

Job costing software — Trade Track, or any decent system — does this automatically. You punch in the quote allowance, punch in the actual spend, and it tells you where you're bleeding. That's the feedback loop that fixes your pricing over time.

Screws, plugs, cable ties, glue, fittings, connectors — the stuff you buy in bulk and use across multiple jobs. This is where most tradies lose track completely. You grab a handful of screws for one job, a handful for the next, and at the end of the quarter you've burned through five boxes of 12g Tek screws and nobody charged any of them to a job.

You don't need to track every single screw. But you do need a rough handle on your consumable burn rate. Buy a month's worth, track what you use, and add a consumables line item to every quote. Even 5% of materials cost covers most of it. The alternative is eating that cost in your margin every month and wondering why profit's tight.

Here's what I'd do if I were starting from scratch on inventory:

1. 1**Do a stocktake.** One Saturday morning, go through the van, the shed, the trailer, and the workshop. Write down everything that's not been touched in three months. That's your dead stock — price it to move or write it off.

1. 1**Start logging materials per job.** Every job that starts gets a materials list. Every job that finishes gets an actuals list. The gap between them is your data.

1. 1**Set a reorder trigger.** When you use the last of something you need weekly — cable ties, saddles, tape, connectors — note it before you put the empty box in the bin. That one habit stops the "I'll grab it next time" cycle.

1. 1**Use the software you've already got.** Trade Track lets you track materials against quotes and actuals on every job. The feature's already there — most tradies just don't use it because nobody told them it mattered. It matters.

Trade Track helps Australian tradies track job costs, materials, and margins in one place — so you know what every job actually cost. [No credit card required · 7-day free trial]