Marketplace Advisor

Strategic frameworks for two-sided and multi-sided marketplace founders, operators, and product leaders. Marketplaces have distinctive economics — most ecommerce / SaaS playbooks don't translate.

Keywords

marketplace, two-sided market, three-sided market, multi-sided market, supply, demand, liquidity, take rate, network effects, chicken and egg, GMV, repeat rate, fill rate, supply density

Clarify First

Before scoring, confirm these inputs. If any is unknown or vague, ASK — do not assume:

• ] Measurement unit — whole marketplace or one liquid segment (city/category)? Liquidity beats GMV; a blended global number can hide a broken core (sets what the score actually describes)
• ] Category + take rate — benchmarks vary widely (Etsy ~6.5% vs Uber ~25-30%), so the take-rate-sustainability dimension is meaningless without the category
• ] Supply, demand, and fill rate — drive the liquidity and balance dimensions, usually the binding constraint
• ] Repeat rate — drives repeat-strength; a low repeat often signals off-platform leakage rather than a healthy marketplace

Stop rule: ask only the 2-3 that most change the output. If the user says "just draft it," proceed and list your assumptions at the top of the score.

Quick Start

bash
python scripts/marketplace_health_scorer.py metrics.json

Scores marketplace health across liquidity, supply/demand balance, take rate sustainability, repeat rate, and network-effect strength.

Core Workflows

Workflow 1: Marketplace Health Diagnostic

1. Capture key metrics: GMV, take rate, supply, demand, fill rate, repeat rate
2. Run: python scripts/marketplace_health_scorer.py metrics.json
3. Identify which dimension is the constraint (usually one of: not enough supply, not enough demand, low repeat, weak liquidity, take rate too high or too low)
4. Plan one focused intervention; don't try to fix all five at once

Time Estimate: 2-4 weeks per diagnostic.

Workflow 2: Chicken-and-Egg Strategy

1. Read references/marketplace_dynamics.md
2. Identify your "constrained side" (usually supply for new marketplaces)
3. Pick a strategy: subsidize the constrained side, single-player mode, vertical wedge, geographic concentration
4. Measure liquidity in the smallest viable unit (one city, one category, one buyer segment)

Time Estimate: 6-12 months for first liquid segment.

Workflow 3: Take-Rate Decision

1. Read references/take_rate_design.md
2. Benchmark category norms (eBay 10-13%, Airbnb 14%, Uber 25-30%, Etsy 6.5%, vertical B2B varies)
3. Decide: high take rate (full-stack with lots of value-add) vs. low take rate (commodity matching)
4. Plan trajectory: most marketplaces raise take rate over time as value-adds compound

Time Estimate: 4-8 weeks for first take-rate decision.

Tools

marketplace_health_scorer.py

Scores marketplace health on five dimensions: liquidity, balance, take-rate sustainability, repeat-rate strength, and supply density.

bash
python scripts/marketplace_health_scorer.py metrics.json
python scripts/marketplace_health_scorer.py metrics.json --json

Reference Guides

• references/marketplace_dynamics.md — Chicken-and-egg, liquidity, network effects, vertical / horizontal trade-offs
• references/take_rate_design.md — Take rate benchmarks, when to raise / lower, full-stack vs lean

Templates

• assets/marketplace_metrics_template.json — Input file for the health scorer with example values

Best Practices

• Liquidity over GMV. A marketplace with $10M GMV across 1,000 cities is mostly broken; the same GMV in 5 cities can be liquid and growing.
• Pick a wedge. New marketplaces almost always start narrow (single city, single category, single segment) and expand.
• Measure repeat early. Marketplaces without repeat are often serving as infrastructure for off-platform transactions (a leakage problem to fix or accept).
• Take rate ratchets up, rarely down. Start low to attract supply; add value-adds (payments, fulfillment, insurance, financing) that justify higher take rate.
• Single-side first when possible. Some categories let you build a tool for one side that becomes a marketplace once liquid (e.g., OpenTable started as restaurant software).
• Beware of weak network effects. Many "marketplaces" lack real network effects — supply on one platform doesn't make demand stickier on that platform. Examine carefully.

Integration Points

• Pairs with business-growth/pricing-strategy — take rate is essentially marketplace pricing
• Pairs with c-level-advisor/cs-fundraising-advisor — marketplace investor expectations differ from SaaS
• Pairs with marketing/landing-page-generator for supply / demand recruitment funnels