Automating Field Service Proof of Work: Parts, Signatures and Evidence That Survives Audit

What does an auditor or a warranty claim actually require as proof of work?

Auditors, warranty assessors and regulators phrase their questions differently, but they are asking for the same evidence, and they give much more weight to a record captured during the visit than to one assembled afterwards. If your system cannot answer each row below from a record created at the time, that is the gap to close, and it is a data model and capture problem rather than a reporting one.

Which Dynamics 365 Field Service records hold the evidence?

The evidence model uses standard Field Service tables. How the installed base, incident types and agreements are designed during a build is covered on our Field Service implementation partner page, so this section concentrates on what each record contributes as evidence and the design choice that decides whether it holds up.

Why do parts go missing from billing, and how do work order products fix it?

When a customer is billed for the wrong parts, or a warranty claim fails because nobody can show what was fitted, the cause is usually the same: parts were written on paper, or Estimated lines were never changed to Used. There is no separate booking product table in Field Service. A work order product line starts as Estimated when the job is planned and becomes Used when the technician confirms it was consumed, and that line can reference the booking on which it was used. Used lines are what drive inventory adjustments and invoicing; Estimated lines left in place make the job look planned rather than done.

• Pre-populate Estimated lines from the incident type, so the technician confirms rather than searches.
• Mark lines Used on the device during the visit, and link them to the booking so a multi-visit job shows which visit fitted which part.
• Add unplanned parts from the technician van warehouse by scan, so stock and evidence come from the same action.
• Block completion of a booking, or flag it for review, when a job type that always consumes parts has no Used lines.
• Record the removed part as well as the fitted one for serialised components, and update the customer asset so the installed base shows what is in the machine now.
• Reconcile Used lines against van stock and the ERP on a schedule; Solzet integrates with your ERP but does not implement Dynamics 365 Finance, Business Central or any other ERP.

What mobile capture flow records the evidence without adding minutes per job?

Technicians abandon evidence capture that feels like paperwork layered on top of the job, and the result is the gap the auditor finds. The design rule is that evidence is a side effect of doing the work: every status change, scan and confirmation the technician already performs writes a piece of evidence, and the only new actions are a small number of required photos and the signature. The flow below is the one we build to on the Field Service mobile app or a canvas app on Dataverse. If technicians work with poor signal, pair it with the durable offline design in our guide to offline field apps that do not lose data.

• 1. Change the booking status on the device. The technician sets Traveling, In Progress and Completed in the app. Each change timestamps the booking, so who attended and when is recorded as a side effect of work the technician already does, not as a separate form.
• 2. Scan the asset to open the job. A QR code or barcode on the machine opens the customer asset and confirms the technician is at the right equipment. A mismatch between the scanned asset and the asset on the work order is flagged immediately rather than discovered at audit.
• 3. Confirm or correct the serial number. The serial on the asset record is shown for confirmation with one tap, or scanned from the rating plate when it differs. A corrected serial is written back to the customer asset, so the installed base stays true for the next visit.
• 4. Work through the service tasks. Tasks come from the incident type, so the checklist is already on the device. Results and measurements go into typed fields rather than a notes box, which makes them evidence rather than prose.
• 5. Mark parts Used by scanning, not typing. Parts expected for the job are already on the work order as Estimated lines from the incident type. The technician scans what was actually fitted to mark it Used against the booking, adds anything unplanned from van stock, and scans the serial of serialised parts, including the part removed.
• 6. Take photos at the points the process defines. The app asks for a photo only where evidence is required, such as the rating plate, the fault before work and the completed installation, and attaches it to the work order with the capture time. Photos taken everywhere else are optional.
• 7. Capture the signature and close the job. The customer signs on the device, the service report is generated from the completed record, and completing the booking locks the evidence against further editing by the field role. With no signal, all of it queues and syncs later with its captured times.

How do you make captured evidence hold up in an audit months later?

Capturing evidence is half the job; the other half is being able to show it has not been changed since. Dataverse gives you the controls, but they have to be configured deliberately before the audit rather than after it.

• Enable Dataverse auditing on work orders, work order products, bookings, customer assets and the columns that carry evidence, with a retention period agreed with compliance.
• Remove edit rights on completed work orders and Used product lines from field and dispatch roles; route corrections through a role that has to give a reason.
• Store the generated service report on the work order as a document, so the version the customer signed is preserved alongside the live record.
• Keep captured time and received time separate on records created offline, so late syncs are explainable rather than suspicious.
• Make the history readable for the people answering the question: our free Easy Audit PCF control shows how a value got to where it is, step by step, and exports the filtered history to CSV.

What can you reconstruct when the evidence was never captured?

Honestly, less than people hope, and presenting a reconstruction as original evidence does more damage than the gap itself. What you can do is assemble what survives from independent sources, state how each fact was established, and keep reconstructed data visibly separate from data captured at the time.

How do you document the evidence gap for an auditor or warranty assessor?

The credible position is transparency: here is what we captured at the time, here is what we reconstructed and from what, and here is what we cannot establish. In Dataverse we model this explicitly rather than editing old records to look complete.

• Create reconstructed records, never backdate them to look original: a reconstruction flag, the source of each fact, who reconstructed it and when, and a confidence level.
• Keep the original gap visible in views and reports, so reconstructed and captured records can be counted separately.
• Attach the source evidence (the stock movement, the email, the scanned sheet) to the reconstructed record.
• Write a short gap statement per affected period: the scope, the method, what could not be established and the change that prevents it recurring.
• Where a physical inspection establishes the current state of an asset, record it as a new, dated inspection rather than as the historical visit.

Should proof of work run on Dynamics 365 Field Service or a custom application?

We recommend the right solution - whether that's Microsoft Dynamics 365, Power Platform, or a custom-built CRM. Some businesses need the Microsoft ecosystem. Others need full control without licensing. We deliver both. If your work orders, assets and scheduling already run on Dynamics 365, Field Service is the natural home for the evidence model above. In our case study on Field Service digitization for a European manufacturer, more than 3,000 pieces of equipment were modelled in Dataverse with serial numbers, warranty information and maintenance schedules, and technicians capture photos, measurements and customer signatures in a mobile canvas app. A custom application on React, Node.js, PostgreSQL or .NET is the better answer when field staff or subcontractors are too numerous for per-user licensing, when proof of work has to be delivered inside your own customer portal, or when you need full control of how evidence is stored and retained.

What does closing a proof of work gap with Solzet involve?

Solzet has 8+ years of Dynamics 365 Customer Engagement and Power Platform delivery and works remotely from Yerevan, Armenia. A proof of work engagement usually starts with a review of one real audit or warranty question against the live data: which rows in the tables above could be answered from captured records, and which could not. From that we adjust the data model, the mobile capture flow and the security and audit configuration, add completion checks, and, where records are already missing, build the reconstruction model and help assemble the evidence. If evidence gaps are one symptom of a larger Field Service programme across old versions and mixed systems, see Field Service transformation on a legacy estate.