Screenshot of the Finance spreadsheet assumption index interactive demo
Screenshot of the interactive demo, on sample data

Finance spreadsheet assumption index

Find the reasoning behind model inputs.

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For
Finance modeling teams
Solves
Key assumptions are buried across spreadsheet files.
Delivers
Model assumption index
Built in
about 5 weeks of creation time, MVP in 6 days
Investment
$12,000 for the MVP, $41,000 for the full product
Run it
Inside your business, or as part of your offer to clients
01

What it does

For finance modeling teams, turn authorized spreadsheets and model documentation into model assumption index.

  1. Locate declared assumptions.
  2. Link source notes.
  3. Flag unexplained changes.
  4. Link proposed outputs to original source records.
  5. Capture reviewer corrections and approval.
  6. Export a versioned model assumption index.

What goes in, what comes out

What the customer puts in
  • Authorized spreadsheets
  • Model documentation

AI drafts, people review. Searchable structured library and data stewardship console.

What the customer gets
  • Model assumption index
02

How it works

The workflow

  1. In
    Start with

    Authorized spreadsheets and model documentation

  2. 1

    The buyer creates a project

  3. 2

    Supplies authorized spreadsheets and model documentation

  4. 3

    Confirms scope and access

  5. Out
    Finish with

    Model assumption index

AI does the heavy lifting, people stay in charge

AI assists these bounded tasks: locate declared assumptions; link source notes; flag unexplained changes. Use only authorized spreadsheets and model documentation and preserve uncertainty in model assumption index. Keep model suggestions separate from verified facts. Link factual outputs to authorized input evidence and show missing information explicitly. Use deterministic checks for counts, dates, identifiers and arithmetic where applicable. A designated reviewer validates consequential outputs and signs off the delivered result.

What your team sees

Key screens: Brief and sources, Finance spreadsheet assumption index, Review and delivery. Use a searchable table or visual gallery with filters for the domain’s important attributes. Open each item into a detail drawer containing source records, ownership and history. Put proposed merges and field changes in a separate review queue. Provide a preview before any bulk export. Open with brief and sources; move into finance spreadsheet assumption index for the detailed task; finish in review and delivery for review and handoff. Show the source record, uncertainty and approval status beside each proposed output.

Accounts and administration

Record ownership, access permissions, change proposals, original-value retention, version history, review dates, bulk import/export and duplicate resolution. Include organization-scoped access, named project owners, review queues, usage limits, export history and retention settings. Never reuse private customer material for other accounts without permission.

Integrations and data access

Accounting exports, invoice records and finance review processes. Source systems, catalog exports and cloud file storage. Start with reversible CSV or file imports and validate identifiers before any direct writes. Begin with uploads and exports of authorized spreadsheets and model documentation. Any named system or connector is a candidate requiring current access and compatibility checks; no live connection is included by default.

03

How we build it

We build with our own AI software development factory, so most implementations take days to a few weeks of creation time, not months. You see working software at every step, and exact timing depends on availability.

  1. 1

    Scoping call

    Day 1

    Thirty minutes on your process, your data and how you want to run it: for your own team, or for your clients. You get a fixed scope and price for the MVP.

  2. 2

    MVP

    6 days

    One buyer segment, one recurring use case; first modules: locate declared assumptions; link source notes. Manual review in the loop. Built by our AI software factory.

  3. 3

    Paid pilot

    7 days

    Accounts, roles, review states, audit trail and the first integration, hardened for two to three paying pilot customers.

  4. 4

    Full product

    3 weeks

    Self-serve onboarding, billing, monitoring and the wider integration set.

  5. 5

    Run and improve

    Monthly

    We host, monitor and improve it for a fixed monthly fee, or hand it over to your team. How the retainer works.

Why we start with an MVP

An MVP, or minimum viable product, is the smallest version that your users can actually work with. It is not a cheap version of the full solution. It is a test, built to answer the questions that decide whether the rest is worth building.

  1. Pick the riskiest assumption. Here: will finance modeling teams use it to solve "key assumptions are buried across spreadsheet files"?
  2. Build only what tests it. One team, one use case, a few core modules. People do the rest by hand for now.
  3. Run a paid pilot. Agree the acceptance criteria, input limits and reviewer responsibilities before starting.
  4. Measure, then decide. Track unsourced material assumptions; reviewer correction minutes; buyer acceptance and repeat purchase. Then expand, change course or stop, with evidence instead of opinions.

MVP scope for this solution. Costed pilot: One organization, one defined input format and one representative pilot batch using authorized spreadsheets and model documentation. Professional judgment, physical inspections, live external actions and production certification remain outside this prototype. Start with one buyer organization and a bounded set of representative inputs. Implement the first two modules: locate declared assumptions; link source notes. Support the third task through an assisted review queue: flag unexplained changes. Handle the remaining required functions manually until validated. Include input upload, source references, user correction, a reviewer approval step and export of model assumption index. Authentication, account isolation, deletion controls and basic operational logging are included. Specialized production certification, live write integrations and broader rollout are not included unless explicitly stated.

After the MVP. After paying customers repeatedly accept model assumption index, automate link proposed outputs to original source records; capture reviewer corrections and approval; export a versioned model assumption index. Add one tested read integration, reusable customer configuration and scheduled repeat delivery. Increase supported formats or teams only when evaluation cases and reviewer capacity cover the new scope. One organization, one defined input format and one representative pilot batch using authorized spreadsheets and model documentation. Professional judgment, physical inspections, live external actions and production certification remain outside this prototype.

What the build depends on. Stable identifiers, an agreed data schema, reversible imports, mapping review and source ownership. Data quality work can exceed model development effort. Obtain representative authorized inputs, an agreed review rubric and a buyer-side owner. Specific scope: One organization, one defined input format and one representative pilot batch using authorized spreadsheets and model documentation. Professional judgment, physical inspections, live external actions and production certification remain outside this prototype.

04

Investment

A planning range to start the conversation, not a quote. You pay per phase, so you can stop after the MVP.

  1. Phase 1

    MVP

    One buyer segment, one recurring use case; first modules: locate declared assumptions; link source notes. Manual review in the loop.

    $12,000 · about 6 days of creation time

  2. Phase 2

    Paid pilot

    Accounts, roles, review states, audit trail and the first integration, hardened for two to three paying pilot customers.

    $12,000 · about 7 days of creation time

  3. Phase 3

    Full product

    Self-serve onboarding, billing, monitoring and the wider integration set.

    $17,000 · about 3 weeks of creation time

Indicative total, MVP to full product$41,000about 5 weeks of creation time · start with the MVP from $12,000

Running costs per month

A rough indication of monthly hosting and AI model costs once it is live, not tested. Real costs depend on usage, file sizes and the models chosen.

StageHosting and infrastructureAI usageTotal per month
MVP and paid pilotabout 3 customers$50–$100$50–$100$100–$200
Full productabout 50 customers$190–$380$350–$700$540–$1,080
05

Run it or resell it

Internally

For your own team

Finance modeling teams run it inside the business: authorized spreadsheets and model documentation in, model assumption index out, reviewed by your people.

For your clients

As part of your offer

Agencies, consultancies and software companies can offer it to their own clients under their brand. We build and maintain it; you sell and deliver it.

Your brand, or this one

Run it under your own brand, or start from this concept style.

  • primary#759127
  • accent#5a54c9
  • surface#edf1e4
  • ink#22201e
Headings
Libre Baskerville
Text
IBM Plex Sans
Voice
Exact, sober, trustworthy
Selling it to your own clients: the go-to-market playbook

Pricing to test

Test USD 500-2,500 for one collection cleanup and launch, followed by USD 100-500 monthly for maintenance within agreed record limits. Larger migrations and complex rights management are separately scoped. Prices are hypotheses. For this buyer, package the first sale around prepare a sample model assumption index from a small authorized set of authorized spreadsheets and model documentation and the defined model assumption index. Record actual review effort before offering a recurring allowance. The commercial pilot fee is distinct from the platform development budget.

Message to test

Find the reasoning behind model inputs. Demonstrate the result with prepare a sample model assumption index from a small authorized set of authorized spreadsheets and model documentation for finance modeling teams. Use a concrete before-and-after example without promising unmeasured savings.

Where to find buyers

Accounting practices and controller communities

Lead magnet

Prepare a sample model assumption index from a small authorized set of authorized spreadsheets and model documentation

The first 30 days

  1. Week 1: interview five prospective buyers from finance modeling teams and inspect how they handle key assumptions are buried across spreadsheet files.
  2. Week 2: prepare prepare a sample model assumption index from a small authorized set of authorized spreadsheets and model documentation using authorized or synthetic material.
  3. Week 3: share the demonstration through accounting practices and controller communities and seek one bounded paid pilot.
  4. Week 4: measure unsourced material assumptions; reviewer correction minutes; buyer acceptance and repeat purchase, review delivery effort and ask for a repeat purchase. This is a validation schedule, not a promise that the full product can be built in thirty days.

Paid pilot

Agree the acceptance criteria, input limits and reviewer responsibilities before starting. Run prepare a sample model assumption index from a small authorized set of authorized spreadsheets and model documentation and deliver model assumption index. Compare unsourced material assumptions; reviewer correction minutes; buyer acceptance and repeat purchase with the buyer's current process on comparable cases; include corrections, missed issues and reviewer time. Seek payment and repeat use. Stop or revise the scope if data access, accuracy or unit economics fail.

Success metrics

Unsourced material assumptions; reviewer correction minutes; buyer acceptance and repeat purchase

Retention and expansion

Build repeat use around model assumption index. Save approved configurations and review decisions with permission, revisit unresolved exceptions and show progress on unsourced material assumptions; reviewer correction minutes; buyer acceptance and repeat purchase. Offer a recurring volume allowance after repeat demand; expand to adjacent tasks only when the buyer asks and delivery quality remains acceptable.

Why clients would pick it

A useful niche taxonomy, customer-approved mappings and accumulated correction history that improve retrieval and reduce repeated cleanup. For this concept, accumulate permissioned examples and reviewer corrections around find the reasoning behind model inputs. The durable asset is reliable task-specific execution and trusted customer configuration, not access to a general-purpose AI model.

Alternatives and positioning

Spreadsheets, shared folders, existing asset or information management systems and manual data cleanup. Position this concept around find the reasoning behind model inputs. Compare it against the customer's current process on the same representative task. This is proposed differentiation; no exhaustive competitor study or uniqueness claim has been established.

Main delivery costs

Import cleanup, extraction, storage, indexing, steward review, duplicate investigation and recurring source updates. Initial validation additionally budgets for representative sample preparation, interviews with finance modeling teams, and qualified domain review of model assumption index. Track model usage, storage, reviewer minutes, exception handling and customer support per accepted deliverable.

06

Safeguards

Reconcile calculations to approved records. Keep proposed entries and payment actions under finance-team control. Never invent missing financial inputs. One organization, one defined input format and one representative pilot batch using authorized spreadsheets and model documentation. Professional judgment, physical inspections, live external actions and production certification remain outside this prototype. Require appropriate access and publication approval. Preserve source material, label AI drafts and make corrections traceable. Measure false positives and missed cases alongside speed.

Get this solution built

Built for you by our AI software factory, MVP in about 6 days. Tell us about your business and how you want to run it: inside your company, or as part of what you offer your clients. We reply within one working day.

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