How to Build a Financial Model for Investors (5 Business Types)

Investors don't read your financial model to see the future. They read it to see how you think. A founder who can explain exactly where every number comes from understands their business. A founder who shows a hockey stick with no underlying drivers does not.

Here's what investors actually want to see, broken down by business type, and the specific metrics that matter for each one.

What investors look at (and what they skip)#

They want: bottom-up projections#

"If we capture 1% of a $1B market" is the sentence that makes VCs stop reading. Top-down projections tell investors nothing about your business mechanics.

Bottom-up means: number of customers x revenue per customer. Where customers come from (which channels, at what cost). How many you lose each month. How much the surviving ones spend over time.

They want: 3-year monthly, not 5-year quarterly#

At pre-seed and seed, investors care most about the next 18-24 months. Monthly granularity matters because it shows cash burn trajectory, seasonal patterns, and when specific milestones hit.

Years 3-5 are important for showing the long-term vision and terminal economics, but everyone knows those numbers are speculative. The first 24 months are where credibility lives.

They want: 3 financial statements#

Revenue projections alone aren't enough. Investors want to see:

1. Income Statement (P&L): Revenue - COGS = Gross Profit - OpEx = EBITDA
2. Cash Flow Statement: Where cash actually goes (operating, investing, financing)
3. Balance Sheet: Assets = Liabilities + Equity, balanced every month

Many founders skip the balance sheet. At pre-seed, you might get away with it. At Series A, you won't.

They want: scenario analysis#

Base case, upside, downside. At minimum. What happens if you grow 50% slower? What if CAC doubles? What if your best channel stops working? Sensitivity analysis showing which assumptions matter most tells investors you've stress-tested your plan.

They skip: 100+ assumption models at pre-seed#

If you're raising a $500K pre-seed round, a 10-tab Excel model with 150 assumptions is overkill. It signals that you spent more time modeling than building. Keep it focused. 15-20 key assumptions, clearly labeled, with benchmarks to justify each one.

SaaS: the metrics that matter#

SaaS is the most common model type investors see, so they have strong expectations.

Key metrics they check:

• MRR/ARR: monthly and annual recurring revenue, with new/expansion/churned breakdown
• Net Revenue Retention (NRR): above 100% means existing customers grow faster than churn. Median for strong SaaS: 110-130% (Bessemer Cloud Index)
• Gross Margin: should be 70%+ for software. Below that signals high COGS (hosting, support)
• LTV:CAC ratio: 3x minimum. Below 3x means unprofitable unit economics
• CAC Payback: under 18 months. Over 24 months is a red flag
• Burn Multiple: net burn / net new ARR. Below 2x is efficient, above 3x raises questions

What makes SaaS models unique: seat-based pricing with expansion revenue. Revenue = ending seats x price per seat. Logo churn and seat churn are different metrics. A company can stay but reduce seats (seat churn without logo churn). Price escalation adds annual step-ups.

Marketplace: the metrics that matter#

Two-sided marketplaces are fundamentally different from SaaS. Investors know this and expect a different model.

Key metrics they check:

• GMV (Gross Merchandise Volume): total transaction value on the platform
• Take Rate: your commission (typically 8-25%, median 15% per a16z Marketplace 100)
• Revenue = GMV x Take Rate: not the GMV itself
• Buyer/Supplier ratio: healthy marketplaces have adequate supply for demand
• Liquidity: what percentage of listings result in a transaction?
• Unit Economics per Transaction: revenue per transaction minus payment processing, fraud, and support

What makes marketplace models unique: you need a dual waterfall. Buyers and suppliers grow at different rates with different acquisition channels and churn patterns. Supply-side churn is often higher (8-15% for long-tail suppliers vs. 3-5% for power sellers). Your model needs to show both sides independently.

E-commerce: the metrics that matter#

DTC e-commerce models are about unit economics per order, not per subscription.

Key metrics they check:

• Average Order Value (AOV): median is $75 across DTC (Shopify data)
• Repeat Purchase Rate: 25-50% is typical, critical for LTV calculations
• COGS as % of Revenue: typically 25-55% depending on category
• Customer Acquisition Cost: across channels (paid social, search, influencer)
• Return Rate: 3-15% for most categories, 20-40% for apparel
• Gross Margin per Order: AOV minus product cost, shipping, fulfillment, returns processing, payment processing

What makes e-commerce models unique: inventory is a balance sheet asset. When you buy $50K of inventory, cash goes down but assets go up. Revenue is recognized when you sell, not when you buy. This working capital dynamic is critical for cash flow projections and most spreadsheet templates get it wrong.

Services: the metrics that matter#

Professional services (consulting, agencies, law firms) have a completely different cost structure.

Key metrics they check:

• Billable Utilization: percentage of total hours that are billable. Target: 65-85%, median 75% (SPI Research)
• Average Hourly Rate: varies wildly by industry ($100-400/hour)
• Revenue per Consultant: utilization x hourly rate x hours per month
• Gross Margin: consultant salaries are COGS in services (not OpEx). Typical margin: 40-60%
• Retainer Revenue Mix: what percentage of revenue is predictable retainers vs. project-based?

What makes services models unique: consultant salaries are your cost of goods sold, not operating expenses. This is the most common mistake in services financial models. OpEx is management, sales, marketing, and overhead. Gross margin measures how efficiently your team generates revenue from their time.

Work-in-progress (WIP) is a balance sheet asset representing unbilled work. It affects cash flow because you've done the work but haven't invoiced yet.

Usage-based: the metrics that matter#

API companies, cloud infrastructure, and metered products use consumption-based pricing.

Key metrics they check:

• Dollar-Based Net Retention (DBNR): same cohort's spend this year vs. last year. Snowflake had 158% at IPO
• Revenue = max(usage x unit price, minimum commitment): if you have committed contracts
• Cost per Unit: your infrastructure cost to serve each unit of usage
• Usage Growth per Customer: are customers using more over time?
• Prepaid Credits: customers buy credits upfront (cash in) but revenue is recognized as credits are consumed (deferred revenue)

What makes usage-based models unique: deferred revenue is a balance sheet liability. Customers pay upfront for credits, but you can't recognize that as revenue until they consume them. This creates a disconnect between cash and revenue that investors will scrutinize.

Common mistakes that kill credibility#

1. Top-down sizing: "1% of a $10B market" = immediate rejection
2. Linear growth rates: real growth decelerates. Use driver-based models
3. Missing cash flow: showing only P&L hides when you actually run out of money
4. Unrealistic margins: claiming 90% gross margin when the industry median is 70%
5. No churn modeling: showing only new customer acquisition without accounting for losses
6. Confusing bookings with revenue: especially for annual contracts and prepaid credits
7. Flat CAC assumption: CAC typically increases as you saturate easy channels
8. No scenario analysis: only showing the optimistic case signals naivety

Build your model by business type#

ModelForge has dedicated engines for all five business types. Each one uses the correct revenue formula, COGS structure, working capital items, and KPI definitions for that business model.

Answer 8 questions, get a complete 5-year model with 3-statement financials, scenario analysis, and sensitivity tornado charts. Free to use.

For a deep dive into SaaS-specific modeling, see SaaS Financial Model Template. Building a two-sided platform? Check the marketplace financial model guide. If you're switching from Finmark, here's the migration guide.