Parts inventory management for repair shops

If you've ever ordered the same screen three times in a week because you forgot you had two in the drawer, you're not alone. Parts inventory feels manageable when you're small, then quietly turns into a money drain before you notice it's happening.

You don't need a warehouse management system. You don't need a barcode scanner. You need something that takes ten minutes to learn and actually gets used — by you and your technicians, every day.

Here's what works in a real shop.

Why parts inventory goes wrong in small shops

The root problem isn't volume. It's that most shops manage parts the way they did when it was one person and a desk. A mental note. A pile in a drawer. A WhatsApp message to yourself you'll deal with later.

When you're the only one who knows where things are, it works — barely. Add a second technician and a front-desk person and it starts falling apart. Parts get used without being recorded. Stock gets ordered twice. Someone grabs the last LCD for a job that isn't the urgent one, and now the urgent job waits three days for a reorder.

The bigger problem is the money. Parts costs are one of the few things in a repair shop you can actually control. Labour is capped by how many technicians you've got. Overheads are mostly fixed. Parts are where the margin lives.

Here's what eats it:

Over-ordering — You're not sure what you have, so you order four screens instead of two. Three sit in a drawer for six weeks, and you've tied up cash that could be doing something useful.

Under-ordering — The opposite. You run out of a fast mover on a Thursday afternoon and the customer's back Saturday morning. You lose the job or pay to expedite an order.

Unrecorded usage — A technician swaps a part, forgets to log it, and your count is wrong. Now you can't trust your own numbers, so you stop relying on them. Vicious cycle.

Shrinkage — The uncomfortable one. Parts that go missing. It's not always theft — often it's a part used for testing and not returned, or dropped in the wrong bin. But unaccounted loss adds up.

A simple system that actually gets used

The key is making it easier to use than to skip. If it's a chore, people skip it. If it's one step that fits naturally into the work they're already doing, it becomes habit.

Step 1: Decide what to track

Not everything belongs in the system. If you're buying a pack of cable ties from the hardware shop, leave it out. Focus on the parts that move money: screens, batteries, charge ports, cameras, boards for the devices you handle most.

The rule of thumb: if it's worth more than a couple of hours of bench time and you use more than two a month, track it.

Step 2: Set the catalogue up once

Every part gets a record: name, cost price, selling price, and a minimum stock level. The minimum is the number below which you reorder. Fast mover, maybe three. Slow mover, maybe one.

The catalogue takes an afternoon to set up and five minutes to maintain after that. Do it properly once.

Step 3: Link parts to jobs

Every time a technician uses a part on a repair, it gets attached to that job. That does three things at once: it keeps your stock count accurate, it puts the part on the invoice so you're actually charging for it, and it gives you a record of what went into each device — useful when a customer comes back.

The friction here needs to be zero. If attaching a part means a separate screen, a separate login, or a bit of paper, technicians won't do it consistently. It has to happen where they're already working.

Step 4: Use low-stock alerts

You shouldn't be manually checking stock levels. The system should tell you when you're running low. Set a threshold per part and let the alerts do the work.

The goal is turning "I'll check the stock" from a weekly job you never get to into a background process you don't think about.

Step 5: Do a weekly count

Once a week — Friday afternoon works for most shops, before you reorder for the following week — physically count your high-value parts and compare against the system. Twenty minutes. If it matches, you're done. If it doesn't, you've got a discrepancy to chase.

Regular counts catch errors before they compound, and they make shrinkage visible fast. A shop that counts weekly spots a problem inside a month. A shop that counts quarterly can be well out of pocket before it notices.

Starting from scratch

Don't try to count everything at once. Pick your top twenty parts by usage, count those, enter them, start tracking. Add more as you go.

A full stocktake is demoralising before you've built the habit. Twenty parts and a working system beats five hundred and giving up on day two. Once the top twenty are working, the rest follows naturally — you add parts as they come in, and within a few months the catalogue reflects your real stock without any heroics.

Don't forget suppliers

While you're at it, record which supplier you buy each part from — and a second source for anything critical. When you run out of a fast-moving screen on a Friday afternoon, you want to know immediately where to get one, not spend twenty minutes digging through old WhatsApp messages.

Accurate usage data also gives you something to negotiate with. "I buy twelve of these a month and I'll commit to one supplier" is a conversation you can only have if you know your own numbers.

How we approached this in Benchworks

Parts were one of the first things we built, because it's one of the things that costs a small shop real money quietly.

The catalogue lives alongside your jobs — you search a part by name while you're building the estimate or invoice for that job and add it there, in the same place you're already working. The cost price and sell price are snapshotted at the moment you use it, so your job costing stays accurate even if you change your prices next month.

Stock levels move on their own: down when a part goes onto a job, back up if it comes off. When a part drops below the minimum you set, we email you — once, not every day until you deal with it. Low stock also shows as a count on your dashboard.

If you're coming from a spreadsheet or another system, there's a CSV import so you can load your existing parts list rather than typing it in.

It's deliberately not complex. The goal was to make the right thing the easy thing, so technicians do it without being nagged.

The numbers that matter

Once you've got a working parts system, you can answer questions you probably can't answer today:

What's my average parts margin this month?
Which parts am I overstocking?
What's my total value of stock on hand?
Which jobs are running at a loss once parts are counted?

These aren't fancy metrics. They're the basics every shop owner should be able to see on demand. Most can't, because the data isn't in one place.

Getting started

You don't need to boil the ocean. Pick your top twenty fast movers this week. Count them. Enter them with a cost price, selling price and minimum stock level. Put a part on the next job and see how it feels.

That's the whole thing. Once the habit's there, it grows.

If you want to try it in Benchworks, sign up — no card, no lock-in, and you can have your first parts tracked before the end of the day.