Proof of work & acceptance: how to avoid disputes over money
Most invoice disputes are not created at the invoice — they start weeks earlier: unclear scope, no records, no acceptance. Five habits that make sure you get paid for what you did.
by Patrick Jerominek · Last reviewed: July 7, 2026
Proof of work is the written record that agreed work was actually performed — and acceptance is the moment the customer acknowledges the work as contractually delivered. If you first hear sentences like 'that was never ordered' at the final invoice, the dispute is usually already lost: not because the work was bad, but because the record is missing. Clean documentation costs a few minutes per job and wins almost every one of these arguments before it escalates.
01Why do payment disputes happen — and what really protects you?
Almost all payment disputes follow the same pattern: scope, duration or condition are contested, and neither side can prove its version. In doubt that hits the business, because whoever claims payment must prove the work. The effective protection is unspectacular: record promptly and in writing what was agreed, worked and handed over.
02What belongs in the work order?
Four things: agreed work, performed work, times and material — one work order per job. Time-and-material work should be recorded immediately, not from memory in the evening: experience says the half hour from the morning goes missing. In DasHandwerk.xhub you record log, times and material right on the work order, even from your phone on site.
03How should you handle extra work?
Get it confirmed first, then do it. The classic: the customer wants 'one more small thing' along the way, and in the end it's ten extra hours — which look like a surprise on the invoice. So: have change requests briefly confirmed in writing before doing them; an e-mail or message is enough. What's done without an order is, in doubt, given away.
04What does acceptance mean legally?
Acceptance is the most important appointment of the job: the customer declares the work essentially as agreed — as a rule the final invoice becomes due, the warranty period starts, and for defects reported later the burden of proof shifts in your favour. Make it a fixed appointment with a short protocol: what was handed over, open items, signature. Ten minutes worth real money.
05What proof of work belongs with the invoice?
For time-and-material jobs the hours and material breakdown, for fixed-price jobs the handover or work protocol. An invoice whose line items explain themselves is questioned less and paid faster. Because times and material are already documented on the job in DasHandwerk.xhub, the proof is no longer busywork but a by-product.
The short version
Five habits prevent most deductions: put the order in writing, log time-and-material work immediately, get extras confirmed before doing them, hold a formal acceptance with a short protocol — and ship the proof with the invoice. Documentation is not paperwork, it is your pay.
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