Kept — the weekly client brief for fractional CFOs

Reviewed from the live landing page at kept-ecru.vercel.app. Pre-launch: waitlist only, no product open, first cohort to be onboarded by hand.

1. The idea

An eight-person accounting firm owner posts to r/Accounting in March 2026: three clients in two months have asked for advisory work, and he keeps saying "yeah let me look into that" while internally panicking. The demand is real and the capacity is not — "I can't just pile 'oh also be a fractional CFO for these three clients' on top of that." Meanwhile fractional CFO demand grew 103% in 2026 and the US market is projected to double from $3.2B to $6.4B by 2028. Clients pay $3,000–$15,000 a month, and what most of them get back is a monthly package.

Kept produces a one-page weekly brief per client, generated from their books and operational data, reviewed and signed by the CFO, sent under the CFO's own masthead. Cash, burn, runway and deltas are computed in deterministic code — "no figure in any brief originates from a model" — and the model drafts only the judgement: what moved and why, which commitments held and which slipped, where effort went against the declared plan, and the one decision that needs making this week with two options and a recommendation. $199/$449/$999 per month for 3/8/18 client workspaces.

2. Fact strip

3. The numbers

4. Why now

A genuine, dated demand wave — on the buyer's buyer. Fractional CFO demand rose 103% in 2026; the US fractional-CFO TAM is $3.2B and projected to double to $6.4B by 2028; the global fractional executive market has passed $5.7B growing 14% annually (2026 market data; Vendux). A rapidly growing population of independent CFOs, all competing for the same $5,000–$7,000/month engagements, is a market where differentiation tooling finds buyers.

What it is not: a forcing function. Nothing compels a fractional CFO to adopt weekly briefing this quarter; no regulation, no platform deprecation, no deadline. Timing scores 6 — a strong tailwind on buyer population, no trigger on buyer urgency.

One supporting signal that the cadence bet is sound: weekly contact is already how the top of the market prices. An accounting firm's public pricing sheet puts "Fractional CFO services" with "weekly or bi-weekly strategy calls" in its $3,000+/month tier, above the $1,250 tier that gets quarterly calls (r/Accounting, Apr 2026, 65↑). Frequency is already the premium axis; Kept is selling a way to hold that axis without the hours.

5. The receipts

"Three different clients in the last two months have basically asked us the same thing... And I keep saying 'yeah let me look into that' while internally panicking bc I have no idea what to charge for any of it or how to scope it or whether my team can even handle it on top of everything else we already do... I can't just pile 'oh also be a fractional CFO for these three clients' on top of that. The opportunity is real, I can see that, but the execution terrifies me." — r/Accounting · Legitimate-Relief128 (owner, 8-person firm) · Mar 2026 · 16 comments · thread

"Tier 3: CFO & Strategic Advisory (Starting at $3,000+/month) — Fractional CFO services · Controller-level oversight · Financial strategy & growth planning · Weekly or bi-weekly strategy calls · Unlimited priority support" — r/Accounting · Key_Marionberry_1827 · Apr 2026 · 65↑, 47 comments · thread

Supporting industry figures: fractional CFOs typically work 10–40 hours per month per client, and most carry 3–6 clients; finance teams spend up to 20% of their time in spreadsheets (2026 practice benchmarks).

The gap in these receipts, stated plainly. Neither receipt is a fractional CFO complaining about building briefs. The first is about capacity and pricing for advisory generally; the second is a price list. I could find no practitioner saying "producing my client reporting is killing me" — and there is a structural reason, covered in §9: almost nobody currently produces a weekly brief, so nobody is in pain from producing one. Fractional CFOs also barely post about their delivery work in public communities, so the receipt channel is thin here the way it was for the consulting reports in this corpus. Pain scores 6 on evidenced capacity strain, not on evidenced brief-building strain.

6. Whitespace

The reporting layer is crowded; the two novel sections are genuinely empty.

Fathom, Jirav, Spotlight, Syft, Reach and LiveFlow all produce management reports and KPI dashboards from Xero/QuickBooks, several with white-labelling — Jirav explicitly lets firms present "under their own brand." That part of Kept is not new.

What no competitor produces, and what the page correctly identifies as the core: the commitment ledger (what was said last week, and where it landed — "the pricing rewrite has now been promised in four consecutive briefs and started in none of them") and drift (declared plan versus actual effort allocation). Every incumbent reports what the numbers did. Neither reports what the client said they would do and whether they did it. That is a different primitive — accountability rather than analytics — and I found nothing selling it.

Two structural choices that strengthen the position:

• "No model ever writes a number." Deterministic computation for every figure, model drafting only judgement, is the right architecture for a document going out under a CFO's professional name — and it is a defensible claim competitors bolting LLMs onto dashboards cannot easily make.
• "No OAuth dance." Uploads, an inbound email address, or a read-only API key. This deliberately sidesteps the restricted-scope OAuth and CASA security-assessment wall that constrains other ideas in this corpus, at the cost of weekly manual friction. For a sub-$1K budget, that is the correct trade and it appears to have been made knowingly.

7. Proof & signals

• The buyer's own price point makes the tool trivially affordable: clients pay $3,000–$15,000/month, sweet spot $5,000–$7,000 (2026 pricing guides). A CFO with three clients bills $9K–$21K/month and pays Kept $199 — about 1–2% of the revenue it is meant to defend.
• The category sustains real software spend: Fathom runs $53/mo for one company up to $400/mo for 25; Jirav starts at $833/month billed annually (2026 comparison). Kept's $199–$999 sits comfortably inside established willingness to pay.
• The buyer population is growing fast (+103% demand in 2026) and is reachable — fractional CFOs are visible, self-identified, and concentrated on LinkedIn in a way agency owners are not.
• Weekly cadence already commands premium pricing in published fractional CFO packages (receipt above).

8. Who you're up against

• The monthly package the CFO already sends — INCUMBENT. Built in Fathom or a spreadsheet, familiar, and — critically — what the client currently accepts. Free at the margin, and its weakness is invisible until a competitor briefs weekly.
• Fathom ($53–$400/mo by client count) — the accountant's reporting standby. Cheaper per client than Kept at scale ($400 for 25 vs $999 for 18).
• Jirav ($833/mo starter, annual only) — three-way statements, scenario modelling, white-labelled. Upmarket, expensive, and modelling-first.
• Spotlight Reporting / Syft / Reach / LiveFlow / Clockwork — the rest of the advisory reporting stack, per-entity or per-firm priced.
• ChatGPT or Claude plus the CFO's own template — the honest DIY. Fails Kept's own test (a model writing the runway number) but costs nothing, and the CFO reviewing every brief anyway may not care.
• Doing nothing — the true default for a CFO at capacity, which is precisely the state the receipts describe.

9. The verdict

Reasons to build

• The commitment ledger is a genuinely novel primitive. Reporting tools measure the business; nothing measures whether the client did what they said. That is both a differentiator and — because brief №34 cites brief №33 — a compounding asset a competitor cannot replicate on day one.
• The price is trivially defensible: $199/month against $9K–$21K/month of billings the tool is meant to defend. This is the cleanest price-to-value ratio of any idea in this corpus.
• The buyer population is growing 103% a year, is self-identified, and is reachable through channels that actually work for a solo founder.
• The architecture is well-matched to the constraints on file: no OAuth dance means no CASA bill, no app-review latency, and no security questionnaire before the first customer — the exact wall that penalises other ideas here.
• "No model writes a number" is a real trust position, correctly identified, and it is the kind of claim that survives a professional buyer's scrutiny when competitors' LLM-summary features do not.
• The go-to-market is already right: first cohort onboarded by hand, at full price, no trial. That is the manual-first validation this engine recommends to almost every idea, adopted before being told.

Reasons to not build

• This is not a time-saver; it is a behaviour change, and the page knows it. Nobody is currently spending Sunday building a weekly brief, because almost nobody sends one — the industry standard is a monthly package. So Kept does not remove existing work; it proposes new work made tractable. That converts the sale from analgesic ("stop this pain") to aspirational ("win engagements you're currently losing") — and aspirational sales to time-poor professionals are materially harder. The honest pitch is competitive fear, not hours saved, and the page's second paragraph already says so.
• The review burden lands on the scarcest resource in the business. Every brief must be read, edited and signed by the CFO. At six clients that is ~24 reviews a month. If a review takes 20 minutes, Kept costs its buyer eight hours a month — and if drafts need real rework, the product recreates the Sunday it promised to remove. This is the single biggest execution risk and it is measurable in the first cohort.
• Tier design is misaligned with how the market actually staffs. Most fractional CFOs carry 3–6 clients. The SOLO tier caps at 3, so the typical practitioner is pushed to PRACTICE ($449, 8 workspaces) while using five — or stays on SOLO and is immediately constrained. The distribution of real client counts sits awkwardly across the tier boundary at exactly the wrong place.
• The addressable market is genuinely small. ~10,000 global providers projected by 2028. Even at a strong 5% share on the middle tier, that is ~$2.7M ARR — and realistic single-digit-percent capture puts the practical ceiling near $1M. Fine for a solo asset; a hard cap on anything larger.
• The cold start is structural. Brief №1 has no commitment ledger, because nothing was promised in a previous brief. The differentiating section is empty for the first two to three weeks of every new client — precisely when the CFO is deciding whether the tool is worth it.
• The data-in problem is weekly, not once. No OAuth means uploads or scheduled exports every single week, per client. That is the friction the product was designed to remove from the CFO's Sunday, reintroduced at the ingestion step. Whoever assembles those exports is doing weekly manual work.
• New audience. Fractional CFOs are not the consulting-firm founders the existing outreach pipeline reaches. The distribution asset that partially rescues other ideas in this corpus does not transfer here — this audience gets built from zero, which is the most expensive input on the constraint list.

10. Founder fit

The idea demands: distribution 8/10 · domain 7/10 · sales 6/10 · technical 6/10 · capital 3/10

Best for: someone who can reach fractional CFOs at volume and is willing to hand-produce briefs for months while the ledger primitive proves itself.

The Rui check. The archetype fit is good: niche vertical, recurring revenue, B2B, compounding switching costs (a client's accumulated commitment ledger is real lock-in), buildable solo. Technical demand is the lowest of any idea here (6) because the hard part is editorial judgement and deterministic finance math, not infrastructure — and capital demand is lowest too (3), because the no-OAuth architecture avoids the certification wall. On constraints alone this is the most buildable idea in the corpus.

The problem is singular, and it is the channel:

• Distribution 5 vs. demand 8, with no transferable asset. Aether's pipeline talks to consulting firms; Kept needs fractional CFOs. That is a new audience built from zero, and distribution is already the weakest axis on file.
• The audience has to be built before anything is sold. Nothing else on the constraint list blocks this idea — the architecture avoids the certification wall, technical demand is low, the price is trivially justified. The whole risk sits in reaching a population of fractional CFOs the founder currently has no route to, and that work has to happen before the first cohort, not alongside it.
• Goal check: $5K MRR needs ~25 customers on SOLO or ~11 on PRACTICE, out of a global population near 10,000 — under 0.3% share, the friendliest arithmetic in the corpus. The constraint is the channel, not the count.

11. Value ladder

12. The plan

The plan on the page is already correct: publish a real brief weekly, onboard the first cohort by hand at full price, no trial. Three amendments the research argues for.

Measure the review minutes, not the generation minutes. The product's whole promise is that the CFO's Sunday disappears. The number that decides whether that is true is how long a CFO spends editing each draft before signing. Instrument it from brief one. Under ten minutes and the pitch holds; over thirty and the product is a Sunday with extra steps.

Sell against the competitor, not the clock. The receipts show fractional CFOs are capacity-constrained but not brief-building-constrained. The pitch that lands is the page's own second line — a CFO who briefs weekly beats one who sends a monthly package — aimed at renewal season and competitive displacement, not at hours saved.

Solve the cold start explicitly. Brief №1 has no ledger. Give the onboarding a "what did they commit to this quarter" intake so the first brief ships with a populated ledger drawn from the CFO's existing knowledge, rather than showing an empty box in the one section that differentiates the product.

Hardest part: judgement quality at the point of signature. Numbers being deterministic solves the trust problem for figures; the recommendation ("Option A, $18,000 against seven weeks of a four-person team is not close") is where a wrong call costs the CFO their credibility with a client. That paragraph is the product.

13. Napkin math — year one

Weakest assumption: the 400 reached. Every other idea in this corpus borrows an existing warm pipeline; this one does not, and the model quietly assumes an audience that has to be built first. Second weakest: retention past month three, which is when the novelty of the ledger has worn off and the weekly review burden has not.

Goal gap: exit run rate ~$2.4K MRR against $5K — closer than most, and closable with roughly double the cohort.

14. The ceiling

$600K–$1.5M ARR: a few hundred practices at $200–$450/month against a global population near 10,000 providers. This is a small, well-defined market and the ceiling reflects that honestly. Two expansions could raise it: the same brief sold to fractional COOs and operating partners (identical structure, different metrics), or moving from a CFO tool to a client-facing accountability product sold to the operating company itself — where the commitment ledger, not the finance summary, is the thing being bought. The second is a bigger market and a different company.

15. Playbook prompts

• Build plan: "Read reports/2026-09-01-kept.md. Spec the first-cohort manual pipeline: intake for the cold-start commitment ledger, the weekly data-collection loop without OAuth, and the review-minutes instrumentation from §12."
• Roast: "Read reports/2026-09-01-kept.md and roast it as (a) a fractional CFO with five clients who already sends a monthly Fathom pack, (b) a founder receiving the brief who thinks weekly is too often, (c) Fathom's product lead. No mercy."
• Money model: "Read reports/2026-09-01-kept.md. Re-cut the tiers against the finding that most fractional CFOs carry 3–6 clients, and model the revenue difference between a 5-workspace SOLO and the current 3."

16. Verdict & next move

BUILD · medium confidence — build the cohort, not the software

The commitment ledger is a real invention. Every reporting tool in this market measures the business; none measures whether the client did what they said they would, and the compounding version of that — promised in four consecutive briefs, started in none — is the kind of section a founder reads twice and a CFO gets credit for. Priced at $199 against $9K–$21K of monthly billings, and architected to avoid the certification wall that penalises the rest of this corpus, the economics and the constraints both work.

The reservation is not about the product. It is that Kept sells a behaviour change — weekly briefing to a profession that briefs monthly — which makes the sale aspirational rather than analgesic, and puts the review burden on the CFO's scarcest hour. That is testable in the first cohort and nowhere else. The tier boundary is also wrong: most fractional CFOs carry 3–6 clients and SOLO stops at 3.

Next move: run the cohort exactly as planned, and instrument one number — minutes the CFO spends editing each brief before signing. Under ten and this is a business; over thirty and it is a Sunday with extra steps. Then move SOLO to five workspaces before the pricing page hardens. Cost: the cohort you were already going to run, $0 extra.

The standing caveat: every verdict in this corpus has landed on the same constraint — distribution, not building. Kept has the friendliest customer arithmetic of any idea here (~25 subscribers) and the weakest existing channel (a fractional-CFO audience that does not yet exist). Those two facts point in opposite directions, and which one dominates is decided by whether the audience-building work gets done before the product does.