How to Get Your First 100 Users on a Marketplace

What Is the Cold Start Problem?

The cold start problem is the circular dependency every marketplace launches into: buyers only come for supply, suppliers only stay for buyers, and at zero users both statements are true simultaneously. The escape is never symmetrical — you pick one side, fill it by unscalable means, and use it to pull the other.

The target has a name: liquidity — in Andreessen Horowitz's marketplace glossary, the reasonable expectation that a listing sells or a buyer finds what they came for. The same glossary notes platform take rates run from low single digits to the mid-30s percent, but none of it is collectable at zero liquidity. Everything in this playbook is a means to that one end.

Which Side Should You Recruit First?

Supply, in almost every category. The asymmetry is behavioural: listing costs a supplier little and pays off whenever a buyer arrives, so suppliers tolerate a quiet start; buyers give a marketplace exactly one chance to be useful. Fifty patient listings can wait for demand — fifty disappointed buyers are gone.

The exception is an existing audience. If you already own the demand side — a newsletter, a community, a client base that trusts you — invert the sequence and recruit supply against demonstrable buyers. That is the position to check honestly before choosing, and the decision tree is short.

Do you already own an audience on one side?
  YES, buyers   -> recruit supply against proven demand
  YES, suppliers -> open demand carefully; supply is banked
  NO -> default: supply first
         |
         recruit 20-50 suppliers by hand
         seed their listings personally
         THEN open demand in one small market
         match early transactions yourself

How Do You Get Your First 50 Suppliers?

Personally, one conversation at a time. List the 50 suppliers you most want, ranked by how much their presence would attract buyers, and work the list by message, call and referral. The pitch is concrete: free or discounted membership as a founding supplier, your help creating their listings, and honest numbers about where the marketplace is.

Make listing effortless — do it for them. Build each founding supplier's listing yourself from their photos and details, because a marketplace with 50 complete, well-written listings looks alive on day one and the suppliers cost you hours rather than budget. Founding-cohort perks (badges, permanent fee discounts, first access to features) buy loyalty that outlasts the cold start, and the supplier interviews you conduct while onboarding are free product research.

How Do You Get Your First 50 Buyers?

Go where the niche already gathers: the communities, groups and forums where your buyers ask for exactly what your supply offers, and show up as a useful participant with specific listings, not a logo with a launch post. In a properly constrained market there are only a handful of such places — that is the sign your constraint is right.

Well-structured listing pages compound this. Each listing that answers a specific search — service, place, price — is a small door into the marketplace, the same mechanism that powers a good SEO landing page; intent-rich pages become your cheapest durable channel. And for the first weeks, close the loop personally: when a buyer enquires, walk them to the right supplier yourself. Concierge service to buyer number ten is how you earn buyer number fifty.

What Is Single-Player Value and Why Does It Help?

Single-player value is usefulness one side gets before the other side shows up: a supplier's listing that doubles as their booking page, a portfolio they can share anywhere, a price calculator, a directory entry that ranks in search. It breaks the circular dependency by giving the early side a reason to arrive and stay that does not depend on liquidity.

Choose one cheap single-player hook and build it into onboarding rather than treating it as a feature project. A supplier who uses their marketplace page as their public presence keeps it current, links to it, and quietly markets you — the marketplace layer then activates on top of behaviour that already exists. The hook also softens the quiet weeks: a supplier getting standalone value has a reason not to churn while demand catches up.

How Do You Measure Whether the Loop Is Working?

Liquidity metrics decide everything in the first hundred users, and none of them is a sign-up count. These four, reviewed weekly, tell you whether you have a marketplace or a mailing list.

When Should You Not Launch Wider?

Do not widen while the loop leaks. If fill rate is low, buyers are bouncing off supply that does not match; if repeat rate is low, the first transaction is disappointing someone. Expanding geography or category at that point multiplies the leak — the marketing spend brings users into a loop that loses them, which is how the 29 percent who ran out of cash in CB Insights' post-mortems spent their runway.

Set expansion thresholds before launch and hold to them: for example, fill rate above half, repeat behaviour visible, and supplier churn flat for four consecutive weeks in the constrained market. Expansion is then a decision the data makes. This is also when monetisation earns attention — a loop that clears thresholds can carry a take rate, and the sequencing lives in how to monetise a marketplace.

What Mistakes Waste the First Hundred?

The cold-start mistakes are consistent enough to name, and most of them are impatience wearing a strategy costume.

• 1. Launching both sides at once, everywhere — thin supply spread invisibly across a wide market reads as an empty product.
• 2. Counting sign-ups — a thousand registrations with no transactions is a landing page, not liquidity.
• 3. Paid acquisition before fill rate — ads pour buyers into a loop that cannot serve them yet.
• 4. Automating matching too early — founder-led matching is your richest learning channel; keep it manual until it hurts.
• 5. Treating founding suppliers as rows in a CRM — the first fifty deserve concierge onboarding and permanent recognition.
• 6. Widening on a good week — one strong fortnight is noise; thresholds held for a month are signal.

PINCLER's Perspective on Marketplace Launches

PINCLER is an AI-first custom software development studio, and the launch pattern above shapes how we scope marketplace software: a two-sided marketplace MVP ships in 20–30 days at $1,800–$2,500 fixed precisely so the founder's time and money stay pointed at supply recruitment and matching, not at a six-month build. Across PINCLER's 79 documented projects — median $1,450 and 13 days, all fixed-price between $500 and $2,500 — the two-sided builds succeed when the constraint and the supplier list exist before the code does.

The phasing mirrors the playbook: version one carries the loop, and the growth features — referral schemes, supplier analytics, automated matching — arrive as later fixed-price phases only after the liquidity metrics clear their thresholds. The dataset behind those numbers is public at what you can build; it is also why we would rather quote a smaller first phase than sell a platform to a founder who has not yet matched five transactions by hand.

Bottom Line

The first 100 users on a marketplace are recruited by hand: supply first, one small market, founder-matched transactions, and liquidity metrics as the only scoreboard. Software's job is to make that loop cheap to run — which is why the MVP should ship in weeks, not quarters. Hold the constraint until the numbers release it, and the second hundred users arrive far more easily than the first. When your supplier list is written, a free 30-minute call will scope the build around it.