Construction
Meet Kos, the last finance hire your next job needs.
For general and specialty contractors. Sub pay apps, lien waivers, certified payroll and supplier invoices, checked line by line the same day.
Kos reads all 812 pages of Ridge Electric’s pay app #14, ties out the distribution and generator lines, and flags switchgear billed ahead of the work, Hollis Supply’s missing lien waiver and retainage held at 2.5% where the contract keeps 5%. It recommends $754,300 of the $1,374,750 requested, drafted in NetSuite for your approval.
Procure-to-pay: Calder Power emails a milestone invoice to the AP inbox. Kos enters it as a bill in your ERP, matches it to PO-4512 and the signed factory test report, codes it, flags $4,860 of freight that isn’t on the PO, and saves the bill at $486,000, pending your approval.
Maya invites Kos to a video call and walks it through a bill on screen share, Kos asks who to tell when a bill doesn’t match the PO, then replays the workflow on a new bill in the ERP sandbox while she watches: it finds the prepayment already went out, tells the requester on Teams, and leaves the bill pending your approval.
Customers and investors
The Problem
Your cash rides on the pay app. Nobody has time to check it.
Three problems contractor finance teams describe, and who feels each one most.
Subs bill ahead of the work
A line billed at 62% with 41% in place, payroll hours the daily reports don’t show, a waiver that never came. Once it’s in your G703, it’s yours.
Felt most by project accounting
Supplier invoices don’t match
Copper billed above the PO price, a delivery ticket nobody can find, the same invoice twice. Every exception lands on a person.
Felt most by AP
You press send and hope
Your pay app is due to the GC today. One missing waiver or unsigned change order and it comes back, and the cash slips a month.
Felt most by the CFO
At Scale
Every new job adds a desk.
One site fills one desk. Each row is one site’s month of documents. The line is the team.
The close slips. The paper triples and the team finds one more analyst. The talent pool is tiny, so site 3 waits for the weekend.
Lender draws wait on backup. The construction monitor asks for the waiver log and the stored-materials backup. Both sit in inboxes across six sites.
Overbilling is found after it is paid. No one has the hours to hold each pay application against the field report. A line billed at 71% with 58% in place is paid in full on Friday.
Illustration. One row is one site’s month of documents, and the team adds one analyst per step. At 12 sites, the line billed at 71% is pay app #14’s switchgear line.
What Finance Teams Tell Us
It’s the most critical part of the construction project. Like if people don’t get paid, there’s no project.
I just press send and I’m like, hopefully they don’t find that one.
I’ve gone from being able to handle my job to sort of rubber stamping, because there’s just no way in hell I can actually do it accurately.
Nobody in their right mind has the time to review it. So they’re getting scammed and things are getting missed.
The Solution
Kos checks it all, the day it lands.
The answer to each problem above: every sub pay app checked, every supplier invoice matched and your own pay app out on time.
Billing review
Subs stop billing ahead of you. Kos checks their G702/G703 against the subcontract, SOV, change orders, retainage, waivers and certified payroll. At STACK, 85% of job spend flows through GC pay apps.
Learn more: Billing reviewProcure-to-pay
Supplier invoices match. Kos works right in your ERP with its own login, matching each invoice to its PO and delivery ticket and coding it to the job. You approve before anything posts.
Learn more: Procure-to-payTeach Kos
No more pressing send and hoping. Show Kos how your pay app package comes together once on a screenshare, and it runs it that way every month.
- WIP schedule
- T&M tickets
- Lien waiver log
How It Works
Forward the sub’s pay app. Kos reads every line.
Nothing new for your team or your subs. The pay app goes to Kos the way it goes to a colleague, and comes back reviewed the same day.
Forward the sub’s pay app
Email Kos the pay app like you would a colleague, or ask it in Slack, Teams, iMessage or on a call.
Kos reads every page
The G702 and G703, the schedule of values, lien waivers, certified payroll and daily reports, each line checked against the subcontract and past pay apps.
Kos flags what doesn’t tie out
Work billed ahead of the field, missing sub-tier waivers and payroll that doesn’t match the daily reports come back with the page and clause behind them.
Your pay app goes out on time
A line-by-line review in your Excel format, commentary to the sub, and the entry drafted in your ERP for your approval.
What It Catches
What Kos flags on every sub pay app.
Each flag comes back with the page and clause behind it. What you recover is your call.
Billed ahead of the work
A sub’s percent complete billed past what the field report shows in place.
Field report
Missing lien waivers
Sub-tier suppliers paid without the conditional waiver the subcontract requires.
Lien waivers
Retainage math
Retainage held below the subcontract’s rate, or released before it’s due.
Retainage
Stored materials without backup
Materials billed as stored with no bill of sale, insurance or location.
Stored materials
Payroll that doesn’t add up
Certified payroll hours that don’t match the invoice or daily reports.
Daily reports
Change orders billed early
Change-order work billed before the change order is signed.
Change orders
In Your ERP
Forward the invoice. Kos works it in your ERP.
Kos works inside your ERP with its own login, like a new hire, whether that’s NetSuite or another system. Nothing to install, and nothing posts until your team approves it.
The invoice lands in the AP inbox
Crestline Supply emails INV-58817 to the AP inbox, where Kos has its own address. Or forward it to Kos as you would to a colleague.
Kos matches the PO and receipt
Kos opens PO-2291 and the signed delivery ticket in your ERP and ties both lines to what was ordered and received on the East Tower job.
Kos codes it and flags the price
East Tower, cost code 26-0533, GL 5100. The copper is billed at $9.85 a foot where the PO says $9.40, so Kos flags $5,400 and recommends $135,440.
Drafted for your approval
The bill waits as pending approval with the flag noted. Nothing posts until someone on your team approves it.
Not New Software
Kos exists where your team already works.
Kos has its own email address and accounts, like anyone you hire. Forward it a sub’s pay app, ask it about a change order in Slack, text it about your pay app or bring it into a call. Nothing to install.
Invite Kos to a Zoom, Google Meet or Teams call and share your screen. Show it how you code an invoice to a change order once, and it codes the next one the same way.
Instead Of
More hands, more tools, or one hire.
What contractors reach for today, next to a colleague who reads every page.
| Compared on | More hires | Outsourced AP | Project software | Frontier LLMs | Kos |
|---|---|---|---|---|---|
| Time per pay app | Days of accountant time | A batch, days later | Depends on setup | Hours of prompting and checking | Same day |
| What gets read | A sample of the backup | What you send them | The fields it’s set up for | The pages you upload | Every page, against the subcontract |
| Where the work lands | Spreadsheets and email | A report, next week | Another app | A chat reply | Your Excel, inbox and ERP, once you approve |
| How you work with it | Hire, train, retain, per job | Engage, wait, pay by the hour | Learn, integrate, roll out per job | Build, prompt, check every pay app | Email, Slack, a call |
| What it takes to start | Months of hiring | A statement of work | An implementation | A custom build on the models | Forward one sub pay app |
Outcome
With Kos on the team, every pay app goes out checked.
Kos reads every pay app, invoice and waiver, and your team approves what goes out.
Nothing slips through
Every sub pay app, supplier invoice and waiver gets a full read, so a line billed ahead of the work or a missing sub-tier waiver is held before it reaches your G703, not found when the GC sends it back.
Same-day reviews, partners paid on time
Each sub pay app comes back reviewed the day it lands, so your own pay app goes to the GC complete and on time. Subs and suppliers get paid sooner, and the best crews want your next job.
Hired, not implemented
Kos works in your email, Slack and calls like anyone on your team. Ask it at 11pm how much retainage the GC is holding, and it answers with the page behind the number.
You Stay in Control
Kos does the reading. You make the call.
- A human approves before anything posts.
- Every flag shows its page and clause, so your team can check any finding.
- Kos has its own identity, only the access you give it, and a full audit log.
- Your data stays in your systems.
Who It’s For
Built for the teams that build.
For general and specialty contractors, and the finance teams that bill and pay for every job.
General contractors
Kos checks your subs’ pay apps, lien waivers and certified payroll before they roll into your own G702 and G703.
For the pay-app lead
Specialty contractors
Electrical, mechanical and every trade. Kos matches supplier invoices to the PO and ties out your own pay app, change orders included, before it goes to the GC.
For AP and billing
Contractors running many jobs
Job cost, the WIP schedule and retainage on every job, kept current each month the way your team taught Kos to build them.
For the controller
Questions, answered.
Kos reads every page of a sub’s pay app, the waivers and certified payroll included, not a sample, and shows the page and subcontract clause behind every flag.
Nothing posts until someone on your team approves it. When Kos is unsure about a line, it asks instead of guessing.
There’s nothing to implement. Kos gets a login like a new hire, and your team emails it the pay apps and invoices.
Kos reads your subcontracts and fills out your pay app workbook in your columns. Show it your process once on a screenshare.
Kos works inside your systems under its own identity, with only the access you grant, and every action is logged.
No. They keep sending pay apps, waivers and invoices to the same inbox.
A project accountant takes months to find and covers a handful of jobs. Kos covers every job from the day it starts, to the same standard.
Why Now
The work won’t wait for your next hire.
Nonresidential construction runs at $1.3 trillion a year.
Up 52% since 2019. Commercial and public work is billed month by month, so every dollar of it crosses a contractor’s desk as a pay app to build, check and chase.
$1.3T
a year in US nonresidential construction, August 2026
- $0T
- $0.5T
- $1.0T
- $1.5T
- $0.9T
- $0.8T
- $0.8T
- $1.0T
- $1.2T
- $1.3T
- $1.3T
- $1.3T
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026latest
The industry needs 349,000 more workers this year.
And 456,000 in 2027. Most of this year’s demand is to replace retirees. Crews are short, and so is everyone who bills and pays for their work.
349,000
net new construction workers needed in 2026
- 0K
- 200K
- 400K
- 600K
- 349K
- 456K
- 2026
- 2027projected
Materials cost 11% more than a year ago.
And 59% more than in February 2020. Every price move reaches your desk as a supplier invoice above the PO or a change order, and someone has to check it against what was agreed.
+11%
construction input prices, September 2026 against a year earlier
- 0
- 100
- 200
- 300
- 400
- 231
- 233
- 278
- 323
- 324
- 318
- 328
- 365
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026latest
Public construction is up 58% since 2019.
To $548 billion a year. Federally funded jobs need certified payroll every week from every sub, and it has to tie to the daily reports before your pay app goes in.
$548B
a year in US public construction, August 2026
- $0B
- $200B
- $400B
- $600B
- $348B
- $364B
- $358B
- $392B
- $464B
- $516B
- $535B
- $548B
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026latest
Forward Kos your next sub pay app.
No new software to learn. Email Kos the work and watch it run.