Work sample 08 / 17Job costing and project billing

simPRO progress claims, variations and retention, tied to Xero

How I'd approach a Melbourne commercial electrical contractor that bills large projects from a spreadsheet, so that every progress claim includes its approved variations, retention is tracked to the dollar, and the owner can read a WIP view each month.

Area
Job costing and project billing
Tools
simPRO · Xero · Excel
Typical scope
US$2,500–5,000
Timeline
About 8 weeks, 4 milestones

Work sample: realistic data, not a past client job. Amounts are in AUD and GST is 10%.

01The problem

A commercial electrical contractor runs 46 projects across a year: office and retail fit-outs, school and aged care work, warehouse lighting and EV charging. Quotes and jobs live in simPRO, but progress claims are worked out in an Excel workbook, typed into invoices, and then re-keyed into Xero.

In this sample, the old workbook has 21 of 105 approved variations missing from its claims, worth $291,000 ex GST ($320,100 including GST).

Owners usually notice it in a handful of ways

  1. A variation is approved by email, the work gets done, and the dollar value never reaches a claim
  2. Retention is deducted by the head contractor, then tracked by memory, so the second release is claimed late or not at all
  3. The claim in the workbook, the invoice in simPRO and the invoice in Xero are three different numbers
  4. Nobody can say what has been claimed against a project, or what is left, without opening five tabs
  5. The month-end picture of work done versus work billed is a guess

02The outcome

This is what the setup does and delivers:

  1. Each project is set up in simPRO as cost centres with the contract value, so a progress claim is a percentage per cost centre, not a number typed into a workbook
  2. Approved variations become their own cost centres, ready to claim on the next itemised claim
  3. Retention is deducted on each claim at the contract rate, tracked per project, and listed with the date each release falls due
  4. An approved claim goes to Xero in one step, as an invoice with one line per cost centre, and the monthly tie-out shows simPRO and Xero agree
  5. A monthly WIP report shows, for every live project, cost to date, forecast cost to complete, earned revenue, billed to date and over or under billing
  6. A short SOP so the office raises claims the same way every month
Data flowHow the work flows, from the first record to sign-off
01PROJECTcontract value02COST CENTRES+ variations03CLAIM% per cost centre04RETENTIONheld and released05XEROinvoice per claim06WIPmonthly view6 STAGES · ONE PASS FROM FIRST RECORD TO SIGN-OFF01PROJECTcontract value02COST CENTRES+ variations03CLAIM% per cost centre04RETENTIONheld and released05XEROinvoice per claim06WIPmonthly view

03Scope

Exhibit AScope
DeliverableWhat's includedNotes
Health check of project billingReview of the claims workbook, a sample of live projects in simPRO, and the Xero invoices and bills they produce. Findings, risk list and a fixed quoteUS$300, and the findings are yours to keep. If the findings change the plan, I re-quote before M2
Cost centre and labour rate designA standard cost centre list for commercial electrical work, and cost and charge-out rates by labour typeRates in this sample are illustrative; yours come from your own cost data
Progress claim schedule per projectEach live project loaded with contract value by cost centre, claim basis and a claim dateClaims can be itemised by cost centre. Where a head contractor must approve first, a Request for Claim is used, which does not post to Xero
Variation and retention trackingVariation register, variation cost centres, retention rate and release terms per project, retention registerRetention terms are taken from each contract. How retention appears on the Xero invoice is checked on a pilot claim and agreed with your accountant
Xero invoice and bill tie-outInvoice stages, account codes, tax codes and an optional tracking category; a monthly tie-out of simPRO against XeroSupplier bills post to Xero with each line at quantity 1, so the tie-out compares totals rather than quantities
Monthly WIP report and SOPWIP workbook for live projects, a one-page monthly routine, and a recorded walkthroughCost-to-cost method, with the method written down so your accountant can review it
Not includedReplacing simPRO or Xero, estimating or tender work, and anything inside Xero that is accounting rather than set-upQuoted separately if wanted

Not included: payroll, STP or BAS lodgement.

Exhibit BSample data
ItemVolume
Projects in the 12 months to 30 September 202646 (17 live, 29 complete)
Claimable cost centres (contract and approved variation)310
Progress claims raised in the period520 (29 final claims)
Variations140 (105 approved, 21 awaiting approval, 14 rejected)
Projects with 5% retention22
Contract value$13,477,900 ex GST
Approved variations$1,777,600 ex GST
Months of WIP12

04Walkthrough

4.0 Cost centres and labour rates

Before any project is loaded, the cost centre list is fixed so every project reports the same way and each cost centre points at one Xero revenue account. The codes and rates below are illustrative.

Cost centreXero revenue account (example)Typical claim basis
Site establishment and temporary power4010 Contract revenue: preliminariesClaimed early, usually 100% by the second claim
Switchboards and metering4020 Contract revenue: switchboardsPercentage as boards are built and installed
Containment and cabling4030 Contract revenue: containment and cablingPercentage by level or area
Lighting and emergency lighting4040 Contract revenue: lightingPercentage by level or area
Power and data outlets4050 Contract revenue: power and dataPercentage by level or area
Mechanical services wiring4060 Contract revenue: mechanical wiringPercentage as equipment is connected
Fire detection interface4070 Contract revenue: fire interfacePercentage, balance on sign-off
Testing and commissioning4080 Contract revenue: testingHeld back to the end of the project
Variations4090 Contract revenue: variationsClaimed once approved
Labour typeCost rate (per hour)Charge-out rate (per hour)
Licensed electrician$62.00$118.00
Leading hand$70.00$128.00
Third-year apprentice$38.00$78.00
Cable and data technician$58.00$110.00

4.1 One project, as simPRO holds it

Take School science block, Essendon (Head contractor 3, 5% retention). The contract is $240,100 ex GST. Three variations were approved during the job. In simPRO each is a cost centre alongside the contract cost centres, so the total claimable value is the contract plus approved variations.

Cost centreTypeValue (ex GST)Claimed to dateClaimed (ex GST)Remaining (ex GST)
Switchboards and meteringContract$111,932.0095%$106,335.40$5,596.60
Lighting and emergency lightingContract$118,564.0095%$112,635.80$5,928.20
Testing and commissioningContract$9,604.0015%$1,440.60$8,163.40
Variation V053Approved variation$9,950.00100%$9,950.00$0.00
Variation V067Approved variation$13,500.00100%$13,500.00$0.00
Variation V074Approved variation$7,550.00100%$7,550.00$0.00
Total$271,100.00$251,411.80$19,688.20

Contract $240,100.00 + approved variations $31,000.00 = $271,100.00. Claimed $251,411.80 + remaining $19,688.20 = $271,100.00.

4.2 Variations

Each variation moves through the same steps: raised from the site, priced, approved by the client in writing, then added in simPRO as a variation cost centre. Until it is approved it sits as "Awaiting approval" and is not claimable. Once approved, it appears on the next itemised claim. Where a variation should count towards retention, it is flagged when it is created.

Variation register for this project:

VariationDescriptionApprovedValue (ex GST)StatusOn old workbook
V053Extra data points, tenancy 401 Jan 2026$9,950.00ApprovedNo
V067Additional circuits, level 2 fit-out01 Feb 2026$13,500.00ApprovedNo
V074Luminaire change to client-selected type08 Feb 2026$7,550.00ApprovedYes

Across the full sample, 21 variations worth $438,700 ex GST are awaiting approval. They show on a "chase approval" list rather than disappearing into email.

4.3 Retention

Terms in this sample are common ones: 5% of each claim is held back, half is released at practical completion with the final claim, and the second half is claimed after a 12-month defects period. In simPRO, the retention rate is set on the project, deducted on each progress claim and tracked, and a release is raised when it falls due.

The last five claims on School science block, Essendon, with retention and GST:

ClaimDateTypeClaimed (ex GST)Retention held backRetention releasedNet (ex GST)GSTInvoice totalRetention held after
INV-3077325 May 2026Progress$92,198.40$4,609.92$0.00$87,588.48$8,758.85$96,347.33$9,238.05
INV-3079310 Jun 2026Progress$29,641.00$1,482.05$0.00$28,158.95$2,815.90$30,974.85$10,720.10
INV-3082125 Jun 2026Progress$29,641.00$1,482.05$0.00$28,158.95$2,815.90$30,974.85$12,202.15
INV-3086125 Jul 2026Progress$5,928.20$296.41$0.00$5,631.79$563.18$6,194.97$12,498.56
INV-3091525 Sep 2026Progress$1,440.60$72.03$0.00$1,368.57$136.86$1,505.43$12,570.59

Net = claimed − retention held back + retention released. GST is 10% of the net amount in this sample. GST treatment of retention depends on the contract, so it is agreed with your accountant before go-live.

Retention register, four projects from the sample:

ProjectNameDeductedReleasedStill heldStatusSecond release due
P2548School science block, Essendon$12,570.59$0.00$12,570.59LiveAt practical completion
P2541Apartment common areas, Clayton$15,550.04$0.00$15,550.04LiveAt practical completion
P2511Office fit-out, Heidelberg$20,060.02$10,030.02$10,030.00Complete25 Apr 2027
P2515Showroom refurbishment, Preston West$28,757.51$14,378.76$14,378.75Complete25 Dec 2026

Across all 22 retention projects, $268,094.22 is currently held. 17 are complete with a second release date on the register, and 5 are still live.

4.4 From simPRO claim to Xero invoice

Only approved claims go to Xero. A claim can start as Pending so a second person checks it, and a Request for Claim lets the head contractor approve the numbers before anything posts. When the claim is approved and transferred, Xero receives an invoice built like this:

simPROXeroNotes
Invoice numberInvoice numberSame number in both systems
Job numberReferenceJob numbers carry a J prefix
Date issued, due dateDate, due dateTerms set per project
Each cost centreOne invoice lineQuantity is always 1
Cost centre amountUnit amountAlways the tax-inclusive amount
Cost centre account codeLine accountMapped once, in M1
TaxTax typeXero applies its tax type from the simPRO tax-code mapping
Link to the simPRO invoiceURL on the invoiceLets the office jump back to the claim

Example: claim INV-30762 on Warehouse lighting upgrade, Preston (no retention), dated 25 May 2026:

Xero line (cost centre)QtyUnit amount (inc GST)Ex GSTGST
Switchboards and metering1$9,923.27$9,021.15$902.12
Power and data outlets1$11,091.30$10,083.00$1,008.30
Mechanical services wiring1$17,190.80$15,628.00$1,562.80
Invoice total$38,205.37$34,732.15$3,473.22

Monthly tie-out. Each month the approved claims in simPRO are compared with the invoices in Xero that came from simPRO. In the sample data:

MonthApproved claimsNet (ex GST)GSTsimPRO totalXero totalDifferenceRetention held at month end
Oct 202524$1,059,340.73$105,934.09$1,165,274.82$1,165,274.82$0.00$187,996.11
Nov 202545$1,386,077.48$138,607.81$1,524,685.29$1,524,685.29$0.00$232,360.63
Dec 202543$1,353,846.21$135,384.67$1,489,230.88$1,489,230.88$0.00$261,928.42
Jan 202650$1,019,244.79$101,924.51$1,121,169.30$1,121,169.30$0.00$284,383.28
Feb 202660$954,021.76$95,402.25$1,049,424.01$1,049,424.01$0.00$291,349.87
Mar 202659$895,424.52$89,542.56$984,967.08$984,967.08$0.00$273,232.75
Apr 202646$799,793.68$79,979.43$879,773.11$879,773.11$0.00$276,167.02
May 202654$1,006,003.66$100,600.44$1,106,604.10$1,106,604.10$0.00$278,194.91
Jun 202648$1,102,417.55$110,241.85$1,212,659.40$1,212,659.40$0.00$257,399.61
Jul 202640$971,610.84$97,161.11$1,068,771.95$1,068,771.95$0.00$260,005.72
Aug 202632$644,962.48$64,496.27$709,458.75$709,458.75$0.00$269,363.59
Sep 202619$274,261.47$27,426.16$301,687.63$301,687.63$0.00$268,094.22
12 months520$11,467,005.17$1,146,701.15$12,613,706.32$12,613,706.32$0.00

4.5 Monthly WIP view

WIP uses the cost-to-cost method: percent complete = cost to date ÷ (cost to date + forecast cost to complete), earned revenue = percent complete × contract plus approved variations, and over or under billing = billed to date − earned revenue. A positive number means billed ahead of the work, and a negative number means work done that has not yet been claimed.

WIP at 30 September 2026, the six largest live projects (ex GST, whole dollars):

ProjectNameContract + variationsCost to dateForecast to complete% completeEarnedBilledOver / (under)Forecast margin
P2546Showroom refurbishment, Malvern$1,246,800$951,616$91,97091.2%$1,136,921$1,148,458$11,53716.3%
P2553School science block, Bayswater$597,600$475,964$47,91190.9%$542,947$553,010$10,06412.3%
P2545Showroom refurbishment, Hawthorn$471,850$377,961$21,43494.6%$446,527$429,398($17,129)15.4%
P2526School science block, Clayton$428,000$325,217$11,36896.6%$413,545$408,585($4,960)21.4%
P2547School science block, Dandenong$399,950$325,603$7,42397.8%$391,036$372,485($18,551)16.7%
P2549Warehouse lighting upgrade, Box Hill$395,700$250,968$62,75380.0%$316,549$304,817($11,732)20.7%

Across all 17 live projects at 30 September 2026: contract plus approved variations $5,529,250, billed $5,039,377 and earned $5,083,985. Overall the book is $44,608 under-billed: $40,984 billed ahead of the work on some projects, and $85,592 of work not yet claimed on others.

05Before and after, on the sample data

The same sample is checked before and after, so each fix can be seen against the problem it removes.

Exhibit CChecks
CheckBefore (claims workbook)After (simPRO and Xero)Status
Approved variations that reach a claim84 of 105105 of 105 as cost centresPASS
Claimed to date + remaining = contract + approved variationsWorked out by hand, not checked46 of 46 projectsPASS
Retention deducted = retention released + still heldTracked by memory22 of 22 retention projectsPASS
Second release has a due date0 of 1717 of 17PASS
Approved claims agree with XeroThree separate numbers12 of 12 months, difference $0.00PASS
Billed to date less retention held = net invoiced in XeroNot available17 of 17 live projectsPASS

06Milestones

Exhibit DMilestones
MilestoneWhat happensRough durationWhat is signed offShare
M1 · Health check and designHealth check (US$300), cost centre and labour rate design, claim and retention rules per project, Xero account and tax mappingAbout 1.5 weeksFindings, design and a fixed quote25%
M2 · simPRO configured, 3 pilot projectsCost centres, rates, claim schedule, variation and retention set-up; three projects claimed end to end into XeroAbout 3 weeksThree pilot claims agree in simPRO and Xero40%
M3 · All live projects loaded, claims checkedThe 17 live projects loaded, variations and retention entered, one claim cycle run and tied outAbout 2.5 weeksTie-out at $0.00 and the retention register approved25%
M4 · WIP report and handoverMonthly WIP workbook, SOP, recorded walkthrough and a two-week watchAbout 1 weekFirst WIP report reviewed with the owner10%

The fixed quote follows the US$300 health check, so the price is based on what is actually in your simPRO and workbook. If the health check changes the plan, I re-quote before M2.

Typical scope for this kind of project: US$2,500–5,000.

About 8 weeks, 4 milestones. Your software subscriptions are billed to you by the vendors.

07Handover

  1. Each live project set up in simPRO with cost centres, variation cost centres and retention terms
  2. A variation register and a retention register with release dates
  3. A monthly tie-out sheet comparing simPRO and Xero
  4. A WIP workbook with the method written down
  5. A one-page monthly routine for the office
  6. A recorded walkthrough
  7. Prepared by Manaz Afzal

08Files

A screen from the sample workbook, then every file in the work sample. Select the image to open it full size.

Summary tab of the workbook: the sample size and the figures in this walkthrough, each tied out by a live formula
Exhibit ESummary tab of the workbook: the sample size and the figures in this walkthrough, each tied out by a live formula

simpro-xero-progress-claims.xlsx › Summary

FilesDownload the work sample
FileWhat it isSize
simpro-xero-progress-claims.xlsxWorkbook with 12 tabs (Read me, Summary, Projects, Cost centres, Claims, Claim lines, Variations, Retention, Xero tie-out, WIP 30 Sep 2026, WIP by month, Cost centre list). The Summary tab lines up every figure on this page with a live formula151.3 KB
simpro-xero-progress-claims.pdfThis work sample as an A4 PDF (7 pages)346.7 KB
projects.csv46 projects with contract, approved variations, claimed to date and remaining5.9 KB
cost_centres.csv310 cost centres with value, % claimed and remaining22.2 KB
claims.csv520 progress claims raised in the 12 months, with retention, GST and totals. Projects that started before October 2025 also have earlier claims, which are not in this file74.0 KB
claim_lines.csvClaim lines by cost centre, summing to each claim58.8 KB
variations.csv140 variations with status and whether they were on the old workbook15.9 KB
retention.csvRetention register for the 22 retention projects2.5 KB
xero_tieout.csvMonthly simPRO and Xero tie-out0.7 KB
wip_live_projects_30_sep_2026.csvWIP for the 17 live projects2.1 KB
wip_by_month.csvWIP summary for each of the 12 month-ends1.1 KB

Tell me what’s bugging you and I’ll tell you where I’d look first.

Send a short note on Upwork about what is slowing the business down. I’ll reply with where I’d start, and whether the US$300 Systems Health Check is the right first step.