Finance & FP&A

How to model financial scenarios and sensitivities as DTC Brand Founders

Finance & FP&AFor DTC Brand Founders3 apps12 steps~24 min to set up

Your financial model lives in a Google Sheet that pulls from three other Google Sheets, two of which have broken formulas nobody touches anymore. When your Meta spend spikes or a supplier invoice lands early, none of it flows automatically into your forecast — you manually reconcile Shopify payouts, card statements, and ad invoices every time you need to answer 'how much runway do we have?' You're running sensitivity analysis by duplicating tabs and changing one number, which means by the third scenario you've lost track of which tab is which. Board update is in two weeks and you still don't know what happens to your cash position if you fund the Q3 inventory buy early.

Build this on Starch → See the apps used

Finance & FP&AFor DTC Brand Founders3 apps12 steps~24 min to set up

Outcome

What you'll set up

A live baseline model where your Stripe revenue and Plaid bank transactions update automatically — no manual imports, no waiting on your bookkeeper

Side-by-side scenario comparisons showing exactly how your runway and break-even shift if CAC climbs 20%, you front-load the summer inventory buy, or you delay hiring your second ops hire by a quarter

A budget-vs-actuals view by spend category (paid media, COGS, 3PL, salaries) so you can see which line items are drifting before they blow up your model

The Starch recipe

Apps, data, and prompts

The combination of Starch apps, the data sources they pull from, and the prompts you use to drive them.

Apps used

Scenario Analysis Runway Analysis Budgeting

Data sources & config

Starch syncs your Stripe data on a schedule (charges, payouts, subscriptions) and your Plaid bank transactions on a schedule (categorized expenses, balances). These two sources power the baseline for Runway Analysis and Scenario Analysis. Budgeting pulls from the same Plaid feed to compare actuals against your set targets by category. No manual uploads; the model updates as your data updates.

Prompts to copy

Build me a scenario model with three cases: (1) baseline using my actual Stripe and Plaid data, (2) a case where CAC increases 25% and I have to pull back Meta spend by $15k/month, and (3) a case where I fund the full Q3 inventory buy in June instead of spreading it across July–August. Show runway, monthly net burn, and break-even month for each.

Build me a runway dashboard that shows my real net burn over the last 6 months, separates paid media spend from COGS and 3PL costs, and projects forward 18 months at my current pace. Flag the month I drop below 6 months of runway.

Set up a quarterly budget tracker with categories for paid media, cost of goods, 3PL and fulfillment, payroll, and software. Pull actuals from my Plaid transactions and show me pace indicators — which categories I'm on track in, which I'm running over, and by how much.

Run these in Starch → or paste them into your favorite agent

Walkthrough

Step-by-step

1 Connect Stripe — Starch syncs your charges, payouts, and subscription data on a schedule so your revenue line reflects real collections, not invoices sent.

2 Connect Plaid — Starch syncs your bank transactions on a schedule, automatically categorizing spend across paid media, 3PL, COGS, payroll, and overhead.

3 Open the Runway Analysis app from the Starch App Store and confirm your baseline: net burn over the last 6 months, current cash balance, and the forward projection at your current pace.

4 Review the expense breakdown in Runway Analysis — check that your Meta and Google ad spend is landing in the right category and not getting mixed into COGS.

5 Open the Scenario Analysis app and set your baseline from the Stripe and Plaid sync. This is your 'current trajectory' case.

6 Build a second scenario where you model the Q3 inventory buy landing in June — increase your COGS or supplier payment line for that month and watch the runway and break-even date shift.

7 Build a third scenario where paid CAC climbs 25% — adjust your paid media spend assumption and see how that changes your customer acquisition math and cash burn simultaneously.

8 Open the Budgeting app and set quarterly targets for each spend category: paid media, cost of goods sold, 3PL and fulfillment, payroll, and software tools.

9 Use the variance analysis in Budgeting to identify which categories are already tracking over-pace this quarter — this feeds back into your scenario assumptions so they stay grounded in reality.

10 Ask Starch to generate a narrative summary of the three scenarios — 'Write a one-paragraph summary of each scenario for my board deck, including runway date, peak monthly burn, and the key assumption that drives the difference.'

11 Set a weekly refresh so your dashboard updates automatically; when you open it on Sunday night before a Monday board call, the numbers reflect Friday's close, not last month's close.

12 Share the scenario output directly with your investors or co-founder — no rebuilding the model in a new deck, no reconciling two versions of the spreadsheet.

See this running on Starch

Connect your tools, describe what you want, and the agent builds it. Closed beta is free.

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Worked example

June 2026 Q3 Inventory Timing Decision

Sample numbers from a real run

Cash on hand (Plaid)	410,000
Monthly Stripe revenue (trailing 3-mo avg)	87,000
Monthly net burn — baseline	51,000
Q3 inventory buy — spread (July + August)	68,000
Q3 inventory buy — front-loaded (June)	68,000
Baseline runway (months)	8
Front-loaded scenario runway (months)	6
CAC +25% scenario monthly burn delta	14,000

You're sitting on $410k in cash with a trailing 3-month average of $87k in Stripe revenue and $51k in net monthly burn — baseline runway of about 8 months. Your 3PL wants you to commit to the full summer inventory buy early to lock in pricing; that's a $68k payment landing in June instead of spread across July and August. In the Scenario Analysis app, you run the front-loaded case: June burn jumps to $119k, cash drops to $291k at month-end, and runway compresses to 6 months instead of 8. That's the real cost of early commitment — not just the cash out, but the cushion you lose if Q3 sell-through disappoints. You run a third case: what if your Meta CAC climbs 25% this summer, adding roughly $14k/month in incremental paid spend? Combined with the front-loaded inventory buy, you're at 4.5 months of runway by September — that's a fundraise conversation you need to start now, not in October. Starch surfaces all three side-by-side, sourced directly from your Plaid and Stripe syncs, so when your co-founder asks 'which number are we using?', you're both looking at the same live model.

Measurement

How you'll know it's working

Net monthly burn (separated: paid media vs. COGS vs. 3PL vs. payroll)

Runway in months at current pace and under each scenario

Blended CAC vs. LTV ratio and how each scenario assumption moves it

Inventory COGS as a percentage of Stripe gross revenue (quarter-to-date)

Budget variance by category — specifically paid media over/under vs. quarterly target

Comparison

What this replaces

The other ways teams handle this today, and how the Starch version compares.

Google Sheets + manual Shopify/Stripe exports

Free and familiar, but every scenario update requires a manual data pull — when your ad spend shifts week to week, your model is stale the moment you close the tab.

Mosaic or Runway (FP&A SaaS)

Purpose-built FP&A tools with polished UI, but they're priced for Series B finance teams and don't connect your ad platform spend or inventory timing without additional manual mapping.

QuickBooks + accountant handoff

Gives you clean books, but scenario modeling still happens outside QBO and you're waiting on your bookkeeper's availability every time you need to update an assumption.

Excel with Power Query

More automation than vanilla Sheets, but building and maintaining the Stripe and Plaid connectors yourself is an ongoing engineering tax, and sharing live scenarios with co-founders or investors means emailing files.

On Starch RECOMMENDED

One platform — scenario planning, runway analysis, quarterly budgeting all running on connected data. Setup in plain English; numbers stay current via scheduled syncs and live agent queries.

Try it on Starch →

FAQ

Frequently asked questions

Does Starch actually pull from Shopify, or just Stripe and Plaid?

Starch connects directly to Stripe (synced on a schedule) and Plaid bank feeds (synced on a schedule). Shopify is available from Starch's integration catalog and the agent queries it live when your app needs it — so you can build a custom surface that combines Shopify order data with your Stripe payouts and Plaid transactions. The Runway Analysis and Scenario Analysis starter apps are built around Stripe and Plaid as the baseline; you can extend them to pull Shopify data by describing what you want.

Can I model inventory timing and COGS, or is this just a cash flow tool?

You can model anything you can describe. The Scenario Analysis app uses your Stripe and Plaid data as a baseline and lets you adjust any assumption — COGS as a percentage of revenue, a one-time supplier payment hitting in a specific month, seasonal inventory builds. You tell Starch what the scenario is in plain language and it builds the model. It's not locked to a cash-flow template.

How current is the data in the model?

Starch syncs your Stripe and Plaid data on a schedule, so your baseline updates automatically — typically daily. You're not waiting for a monthly close or a manual import. When you open your runway dashboard on a Sunday night before a Monday board call, it reflects the most recent sync, not last month's numbers.

Is this a replacement for my accountant or bookkeeper?

No. Starch gives you a live modeling and scenario layer on top of your actual transaction data — it's for making faster decisions, not replacing the person who closes your books and handles tax. Think of it as what you use between monthly closes so you're not flying blind.

I don't use Stripe — my Shopify payouts go directly to my bank. Does that work?

Yes. Plaid connects to your bank account directly and syncs your transactions on a schedule regardless of whether they originate from Stripe, Shopify Payments, or any other payment processor. Your Shopify payout appears as a deposit in your Plaid feed; the runway and scenario models build off that.

What are the honest limitations here?

A few worth knowing: Starch is not SOC 2 Type II certified yet, so if your investors have strict data security requirements, flag that. Starch is a live data surface, not a long-term data warehouse — it's not designed for multi-year archived analytics. And the Budgeting app is currently in development; you can request beta access, but it's not fully live today. The Runway Analysis and Scenario Analysis apps are live and available now.

Can I share the model output with my co-founder or investors without them having a Starch account?

You can export the scenario output or ask Starch to generate a written summary you can drop into a board deck or a Notion doc. For live shared access, your co-founder would need to be added to your Starch workspace. There's no public read-only link for external investors today.