It’s Thursday afternoon and you’ve just finished a boiler swap in a semi-detached in Reading. You wiped the gas hob down, bagged the old unit, ran the commissioning cycle, handed over the Benchmark certificate, got a signature on the paper invoice, shook hands and drove off. Two hours later, while you’re stuck on the M4 heading to the next call, your phone rings. It’s the customer’s wife. She says the new boiler is “making a noise that wasn’t there before” and she’s pretty sure you didn’t actually clean the system out like you’d quoted. She’s heard from a neighbour that the job should have taken at least four hours and you were only there from one until just gone three. She wants £220 off the invoice, or she’s not paying at all.
You know exactly what you did. You arrived at 13:05, you flushed the system properly, you ran the magnetic filter, you fitted the right unit on the spec sheet, you signed out at 15:22. But everything you know is in your head. The paper invoice in her kitchen drawer just shows a date, a description and a total. There’s no timestamp on it. There’s no photo of the old unit you took out, no photo of the new one fitted, no GPS log of your van parked outside her house for two hours and seventeen minutes. You’ve got a hunch she’s already on the phone to her card issuer asking how to claw back the deposit.
If you’ve been on the tools for more than a year or two, you’ve lived some version of this story. A customer who suddenly remembers the kitchen tap was “already loose before you turned up”, a landlord who insists the rewire only covered the ground floor when the quote clearly says both floors, a small commercial client who pays the invoice forty days late and then opens a dispute claiming the work was never completed to standard. The amounts in dispute are usually small enough that you can’t justify a solicitor — £180 here, £640 there, £1,200 for the awkward one — but they add up. Talk to enough sole traders and small Ltd outfits in the UK trades and you’ll hear the same number range over and over: somewhere between £4,000 and £18,000 a year written off to disputes, chargebacks and “goodwill discounts” you didn’t actually want to give.
Why customer disputes happen in the trades, and why you keep losing them
Disputes are rarely about the work itself. They’re about the gap between what you remember doing and what the customer can prove you didn’t do. That gap is your problem, not theirs. In a domestic job covered by the Consumer Rights Act 2015, the customer is entitled to a service performed with reasonable care and skill, within a reasonable time, and matching what was agreed. The burden of showing the service was delivered to that standard sits on the trader. If you can’t show it, the customer can ask for a repeat performance, a price reduction, or in the worst cases a full refund. Trading Standards will, perfectly reasonably, ask you for evidence. “I was definitely there for two hours, you can ask my apprentice” is not evidence.
It gets harder when payment has already gone through a card terminal or a payment app. The customer rings the card issuer, the issuer raises a chargeback under the scheme rules, and suddenly the money is sitting in a holding account waiting for you to defend it. You’ve got a tight window — often fourteen days — to upload proof. If your only proof is a scanned paper invoice and a text message saying “thanks, will pay Friday”, you’ll lose. The issuer isn’t deciding who’s morally right. They’re deciding whether the merchant uploaded enough timestamped, location-bound evidence to satisfy the scheme’s rules. Most small installers don’t, because nobody ever taught them the documentation game has changed.
The B2B side is just as bleak. A small commercial customer who’s slow-paying you can sit on an invoice past the thirty days agreed, then quietly invoke a “quality concern” the moment you start chasing under the Late Payment of Commercial Debts (Interest) Act. Suddenly the conversation isn’t about your statutory right to interest and reasonable recovery costs. It’s about whether you can demonstrate, in writing, that you actually attended on the day you said you did, that you worked the hours you billed, and that the deliverables match the scope of works. If you can demonstrate it, the conversation ends in five minutes. If you can’t, the conversation becomes a six-month tail of email tennis where you’re effectively offering discounts to make the file close.
What the customer is really doing when they dispute
It’s worth being honest about the psychology, because once you see it you stop taking it personally. A small minority of customers are straightforwardly dishonest and will try it on with every trader. Most are not. Most are reacting to one of three things: bill shock at a final figure that landed higher than the rough quote, a small fault that’s appeared in the days after you left, or a household conversation in which somebody else — a partner, a parent, a neighbour who “knows about these things” — has planted the seed that you charged too much or did too little. That seed grows in the absence of evidence. If your handover ended with a paper docket, a verbal “all done” and a wave from the van, the customer has nothing concrete to anchor against the doubt. They’re not lying when they say they’re “not sure” you flushed the system. They genuinely aren’t sure, because you didn’t give them a reason to be sure.
