For consultants
Bill like a firm.
Without becoming one.
Your customers have procurement teams, vendor portals, PO numbers, and Net 60 terms. Your billing has to match that bar. Wrenbase gives you the polished surface of a professional services firm without the overhead of running one.
From
Field & Co Advisors
San Francisco, CA · EIN on file
Invoice
FCA-2042
PO number
PO-2026-114
SOW
Q2 Advisory · Apr 15
Strategic advisory · April
€18,000
Board prep · 8h
€2,400
Travel pass-through
€1,200
Total · EUR
Net 60 · due Jul 13
€21,600
Credibility
The trust your customers hand you,
mirrored in how you bill them.
You charge $250 an hour or $80,000 for an engagement. The invoice that arrives in your customer's procurement queue should look like it came from a firm of that caliber. Not a freelancer.
PO numbers, SOW references, legal entity name, payment terms, multi-currency. The details procurement looks for, all in the right places.
What procurement expects
Legal entity on the bill
Field & Co Advisors LLC, the name in their vendor master, not just a person.
PO and SOW references
On every invoice in the engagement, so AP can match it to the contract.
Procurement-grade terms
Net 30, Net 60, or custom, set per engagement to fit their AP cycle.
Wire and ACH instructions
Included where procurement needs them.
Multi-currency
Each invoice in the customer's currency.
Audit-ready history
Every invoice and payment searchable in Cash Pulse.
One engagement
From deposit to renewal, one engagement tracked.
Deposit at kickoff, milestone at midpoint, balance at final, then a renewal retainer. Every invoice carries the same PO and SOW reference under your legal entity name. The customer's AP team sees the same vendor on Net 60, every time. You see one continuous record.
Engagement
Berlin SE · Q2 strategic advisory
PO-2026-114 · SOW Apr 15 · Net 60 · €80K total
Phase 1
Deposit
$15K · Mar 18 · paid
Phase 2
Kickoff invoice
$20K · Apr 1 · paid
Phase 3
Midpoint
$25K · May 1 · awaiting
Phase 4
Final
$20K · Jun 1 · scheduled
Renewed
Retainer
Jul onward · $12K/mo
Relationship continuity
Every engagement becomes part of
a continuous customer record.
When the next engagement starts, the customer's billing history is already there. Every invoice you've sent them, every payment they've made, every PO they've referenced. The credibility of the last engagement carries into the next.
Their procurement team sees consistency across years. You see one continuous account. The relationship compounds.
Customer account
Berlin SE
5 engagements · €320K lifetime
2024 Q1
€60K
Operating model review
Paid
2024 Q3
€72K
Restructure advisory
Paid
2025 Q1
€18K
Board prep
Paid
2025 Q2
€80K
Strategic advisory
Sent
2025 Q3
€90K?
Renewal in discussion
—
Every engagement, one continuous record.
The project Overview
What the engagement made, as the work happens.
Make an engagement a project and you get this Overview. Profit margin, what's still owed you, and how the budget is holding, in the currency you billed. It's the same page whether you call it a project, an engagement, or a matter.
Roll every engagement up and Cash Pulse tells you the margin across the book and exactly where you stand this quarter.
Berlin SE · brand strategy
Budget: €36,000 · started Apr 1
Profit margin
healthy60%
Collected €21,600 minus spent €8,600, over collected.
Outstanding
1 overdue€14,400
Billed €36,000, collected €21,600.
Budget
on track€27,400 left
Spent €8,600, committed €2,900, of €36,000.
Receivables aging
€14,400
Cash timeline, next 6 weeks
The project Overview, in the currency you billed.
What procurement sees
The invoice that lands in their queue.
Legal entity, PO and SOW references, currency, terms. Every field where it should be.
Bill from
Field & Co Advisors LLC
123 Market St, San Francisco, CA 94103
EIN ****1234 · [email protected]
Invoice
FCA-2042
Issued May 14
PO Number
PO-2026-114
SOW
Q2 Advisory · Apr 15
Engagement
Berlin SE · strategic advisory
Terms
Net 60 · due Jul 13
Strategic advisory · April
€18,000
Board prep · 8h
€2,400
Travel pass-through
€1,200
Total · EUR
€21,600
Wire instructions
Beneficiary: Field & Co Advisors LLC
SWIFT/IBAN on payment page
Entity name and address
Procurement matches the bill to your vendor record by legal name. Wrenbase puts this front and center.
PO and SOW block
The fields AP looks for are in their own labelled block, not buried in the description.
Native currency
EUR end to end. No forced conversion. The customer pays what they expect to pay.
Payment terms visible
Net 60 on the bill itself. The due date computed and shown.
As the practice grows
From solo advisor to a real shop.
The same surface scales from three engagements to thirty.
When
When an engagement crosses $50K
Then
Switch to milestone billing
Bill against PO milestones: kickoff, midpoint, final. Each invoice carries the same engagement reference.
When
When you bring on a second consultant
Then
Bill each consultant's time per engagement
Hourly lines per consultant on the same engagement invoice. Procurement sees one bill. You see each contributor.
When
When you start working across borders
Then
Bill in 20+ currencies
Each invoice tracked in the customer's currency end to end. Cash Pulse shows revenue per currency separately.
When
When you take on your own sub-contractor
Then
Open Wrenbase Intake
Your sub submits through your branded link. Sanctions and fraud checks run before the bill reaches you.
Learn more →When
When the engagement book gets dense
Then
Open Cash Pulse
See which engagements are aging close to Net 60, which deposits are still outstanding, and what revenue lands this quarter.
Learn more →Built for
Independent advisors who bill enterprise.
Every kind of engagement
However you sell the work, it bills the same way.
Deposit up front, milestones through the work, a renewal retainer after. SOW and PO on every invoice, Net 30 or Net 60 to match their procurement. The shape of the engagement changes; the billing rigor does not.
Operating model review
Deposit at kickoff, then billed against SOW milestones. PO on every invoice.
Restructure advisory
Phased billing across a multi-month scope. Each phase invoiced under one engagement.
Strategic advisory
The retainer sends itself each cycle. Net 30 or Net 60 to match procurement.
Board prep
Hours logged, billed to the cap, referenced against the SOW they signed.
Diligence support
Short scope, deposit before work, final on delivery. Entity name on the invoice for the deal file.
GTM strategy
Kickoff, midpoint, final. One engagement record from first invoice to sign-off.
Org design
Diagnostic, design, rollout, each a milestone under the same PO.
Interim / fractional
A steady monthly bill under one engagement. Renews without re-papering the terms.
Workshop / facilitation
Deposit to hold the date, balance after. Each session a line on the same invoice.
Works with the tools you already use
Keep your delivery stack. Wrenbase is the money layer beside it.
You run the engagement in the tools you already know. Wrenbase handles the billing, the PO and SOW references, the currency, and what you collected. Bring your numbers in by CSV import, live now.
Your stack
Where the work gets done. Stays exactly where it is.
Plus Wrenbase
The billing surface procurement pays against.
No rewiring your workflow. Export the hours or amounts from your tool, import the CSV, and bill.
Your words, in Wrenbase
You keep your language. It maps underneath.
You don't learn accounting words to use Wrenbase. What you already call things maps onto the ledger objects that make the margin add up.
| In your practice | In Wrenbase | What it drives |
|---|---|---|
| The client | Customer | Who you bill, with their whole engagement history |
| An engagement, matter, or retainer | Project + recurring invoice | Its own live P&L; the retainer sends itself each cycle |
| Subcontractors or associates | Vendors | Bills in, screened, counted against the engagement |
| Margin per engagement | Project P&L → Cash Pulse | Read live, not rebuilt in a sheet |
Projects · Per engagement, live P&L
Know what each engagement actually made.
Make an engagement a project and the retainer, the overages, the subcontractor costs, and what you kept all land in one view.
Meridian rollout · Overview
on trackProfit margin
60%
Outstanding
$1,000
Budget
$14.6k left
Cash timeline, next 6 weeks
Weeks 1-2 run cash-negative before Meridian's payment lands in week 3. Consider nudging invoice #4.
Common questions
The questions sophisticated customers create.
- My engagement tracker is a spreadsheet. PO numbers, milestones, what's been invoiced. What changes?
- You stop maintaining the spreadsheet. Each engagement in Wrenbase holds the customer, the PO, the SOW reference, the schedule, and every invoice you've sent against it. Open the engagement to see where you stand. If you've got a spreadsheet of past engagements or customers, drop it in and Wrenbase will import it.
- How do I carry PO numbers and SOW references on every invoice?
- Add a PO and SOW reference to the engagement. Every invoice you send for that engagement carries the same reference block. Procurement sees exactly what they expect. Nothing to remember at billing time.
- How do I bill a customer in their currency without confusing my US books?
- Pick the currency per engagement. Bill in EUR, GBP, INR, BRL, JPY, and more. Each invoice issues and tracks in the currency the customer expects. Wrenbase keeps the original currency end to end. No forced conversion.
- How do I look established to procurement without becoming a firm?
- Your invoice carries your logo, your legal entity name, your payment terms, and your wire instructions. The page your customer sees when they pay carries your brand. To their AP team, it looks like the billing surface from a real business.
- What if a customer wants me onboarded through their vendor portal?
- You stay the billing-of-record. Wrenbase holds every invoice you've sent for that engagement with PO and SOW context, so when their AP system asks for proof, you can hand it over.
- Which engagements are funding the quarter?
- Set Net 30, Net 60, or custom terms per engagement. Cash Pulse shows who's paying on time, who's drifting toward the back of the window, and which engagements are actually funding this quarter versus which are still contracted but uncollected. Revenue that's real, not just promised.
- Can I take a deposit before kickoff?
- Yes. Send a payment request for the deposit before work begins. When it clears, kick off the engagement. The deposit lives in the same engagement record as the milestone invoices that follow.
- How do I know what an engagement actually made?
- Make it a project. The retainer, the overage invoices, and the subcontractor bills roll into one view with margin computed live. When the engagement wraps, the number is already there.
The polish of a firm. The overhead of one person.
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