Car-Share Venture: Financial Model Explorer

Overview

This interactive tool provides a comprehensive framework for exploring the financial dynamics of a car-share venture, including pricing strategies, cost structures, and customer lifetime value analysis.

Features

Pricing Strategy — Adjust pricing levers and see 5-year revenue projections, net income, and breakeven timing
Member Build-up — Set new member targets, car fleet size, and marketing spend by year
Cost Structure — Visualize local office costs across billing, processing, marketing, and fixed overhead
Plan vs Actual — Compare planned assumptions against actual operating data with variance analysis
Unit Economics — View gross margin from three perspectives: per use, per member, or per car
Overview — 5-year P&L summary with gross margin and overhead as % of revenue, plus sensitivity analysis via tornado charts and heatmaps
Lifetime Value — Model customer LTV with adjustable margin, attrition, and acquisition cost

Usage

All calculations run client-side with no server dependencies. Adjust the sliders and controls to explore different scenarios.

Pricing Structure

Adjust pricing levers — membership fees, hourly rates, mileage charges — and see how they flow through to 5-year revenue projections, net income, and breakeven timing.

Annual membership fee

$75

Hourly rate

$5.50

Per-mile charge

$0.40

Application fee (one-time)

$25

Trips per member per month

4.0

Attrition rate (annual)

15%

Revenue Breakdown + Members · 5-Year Projection

Net Income Before Tax

Revenue vs Direct (Car) Costs

Adjust pricing levers to explore the trade-off: higher membership fees provide predictable recurring revenue but may suppress sign-ups, while usage-based pricing aligns revenue with demand but introduces volatility. Net Income (shown above) includes local office overhead in addition to car costs.

Member Build-up

Set new member acquisition targets and marketing spend for each year. These values feed into the Cost Structure and Pricing Strategy projections.

New Members by Year

Year 1 — New Members

440

Year 2 — New Members

482

Year 3 — New Members

180

Year 4 — New Members

408

Year 5 — New Members

193

Marketing Spend by Year

Year 1 — Marketing ($)

$10,000

Year 2 — Marketing ($)

$12,000

Year 3 — Marketing ($)

$12,000

Year 4 — Marketing ($)

$12,000

Year 5 — Marketing ($)

$12,000

Car Fleet by Year (End of Year)

Year 1 — Cars

Year 2 — Cars

Year 3 — Cars

Year 4 — Cars

Year 5 — Cars

Member Growth — End of Year Totals

Cars & Members per Car

Marketing Spend vs Cost per New Member

P&L Impact

Revenue Breakdown + Members

Net Income Before Tax

Revenue vs Direct (Car) Costs

Annual Car Costs ($8,680/car)

5-Year Member Build-up Summary

Adjust member targets and car fleet to maintain a healthy members-per-car ratio (typically 15-20). Car costs are $8,680 per car per year. Marketing CAC includes a $20 processing cost per new member.

Cost Structure — Local Office

The local office (Boston) costs break into four categories with different cost behaviours. Car fleet costs (direct variable costs) are shown separately on the Pricing Strategy and Unit Economics panels.

Cost Category Mapping

Category	Driver	Unit Cost	Line Items
Per member	Avg members	$24 / member / yr	Billing & member servicing
Per new member	New sign-ups	$20 / new member	Background checks, processing
Marketing	Annual budget	$10–12K / yr	Marketing spend
Office fixed	None (fixed)	$31–57K / yr	Admin salaries, benefits, space, equipment, phone

Local Office Costs — 5-Year Breakdown by Category

Cost per Member (All-In Local Office) by Year

Customer Acquisition Cost (Marketing + Processing) / New Members

5-Year Detail — Local Office Costs (Revised Plan)

Billing scales linearly with members ($24/yr). Background checks scale with new sign-ups ($20 each). Marketing is nearly flat, which means CAC rises sharply in years with few new members (Year 3, Year 5) — this invites the question of whether marketing spend should be more elastic. Office fixed costs step up in Year 2 as staff grow, then plateau.

Plan vs. Actual — Operating Data

Members (actual)

239

vs ~156 plan pace

Trips / member / mo

1.98

vs 4.0 planned

Utilization rate

30.6%

vs 40% planned

Annualised attrition

22.7%

vs 15% planned

Revenue / use

$43.71

vs $30.80 planned

Members / car

11.6

vs 18.0 planned

Fishbone Decomposition — Margin per Member

Planned · Monthly margin per member

Actual · Monthly margin per member

Variance Waterfall — Where the Plan Broke Down

Hourly vs Daily Use — The Hidden Economics

Actual Performance by Use Type

Metric	Hourly	Daily	Overall	Plan
Hours per use	6.20	16.00	9.62	4.00
Miles per use	24.5	94.0	48.8	22.0
Revenue per use	$42.78	$45.45	$43.71	$30.80
— hourly/daily-cap revenue	$33.12	$44.00	$36.92	$22.00
— mileage revenue	$9.66	$1.45	$6.79	$8.80
Car cost per use	$21.90	$56.53	$33.98	$10.05
Margin per use	$20.89	−$11.08	$9.73	$20.75
Uses / member / mo	1.29	0.69	1.98	4.00
Margin / member / mo	$26.85	−$7.64	$19.22	$83.01

Daily uses tie up 16 hours of car time but generate only $45.45 — the $44 daily cap (8h x $5.50) plus minimal excess mileage ($1.45 avg, since most trips stay under 125 free miles). The car cost for those 16 hours is $56.53, making every daily use margin-negative.

Pricing Response — Daily Rate Explorer

How would changing the daily cap and free mileage allowance affect the economics?

Daily rate cap ($)

$44

Free miles included

125

Per-mile charge (excess)

$0.40

Per-Use Margin — Hourly vs Daily

Blended Monthly Margin per Member at Varying Daily Caps

The average daily user drives 94 miles. At 125 free miles, nearly all trips fall below the threshold. Reducing the free-mile allowance or raising the daily cap directly attacks the daily-use subsidy.

Unit Economics Simulator

Same gross margin % — different lens

Members per car

Monthly car cost ($)

$723

Revenue per use ($)

$30.80

Hours per use

4.0

Uses per member per month

4.0

5-Year P&L Summary

Profit & Loss Statement — 5-Year Projection

Sensitivity Analysis

Which assumptions matter most? Year 3 net income response to changes in key parameters.

Tornado Chart — Impact on Year 3 Net Income

Two-Way: Hourly Rate x Members/Car — Year 3 Net Income ($K)

The tornado chart reveals leverage points. The heatmap shows how two critical variables interact.

Customer Lifetime Value

Monthly margin per member ($)

$90.26

Annual attrition rate

15%

Customer acquisition cost ($)

$43

Cohort Survival Curve — % of Members Remaining

Cumulative Margin per Member Over Time

Comparison — Plan vs Actual

Metric	Plan	Actual	Delta
Monthly margin / member	$90.26	$26.56	-71%
Average lifetime (months)	80	53	-34%
Lifecycle margin	$7,221	$1,401	-81%
CAC (marketing + processing)	$42.73	$47.23	+11%
Net lifecycle margin	$7,178	$1,354	-81%

Even with much lower margins and higher attrition than planned, the lifetime value per member remains positive. The CAC now reflects the full cost of acquisition: marketing budget plus background checks per new member.