How to build a marketplace: what it needs, what it costs and where to start

A marketplace connects those who offer something with those who are looking for it, and keeps a commission: products, professional services, rentals, classes. Technically it is one of the most complete projects, because it has two kinds of user with different needs and other people’s money in between. The good news is that you don’t need to build it all to get started.

The parts of any marketplace

• Sign-up for two kinds of user: those who offer (sellers, professionals) and those who buy or hire.
• Sellers creating and managing their listings or products, with photos, prices and availability.
• Search with filters and, where it makes sense, a map.
• Payment within the platform, with the commission split off automatically.
• Messages between both sides, reviews and email notifications.
• An admin panel to vet sellers, resolve issues and see activity.

Payments are the delicate part

Charging the buyer, keeping your commission and paying the seller means moving other people’s money, and that carries legal obligations. The sensible approach is to rely on a payment provider with marketplace support, which verifies sellers’ identity and splits the amounts without the money passing through your accounts. Decide early when sellers get paid (instantly, when the service is completed, at the end of the month) and what happens with refunds: it shapes a good part of the development.

What changes the quote the most

• The type of transaction: selling a product with delivery is not the same as booking a service on a date or renting by the day.
• How much control you have over sellers: manual verification, documents, contracts or tiers.
• Advanced search: geolocation, real-time availability or recommendations.
• A mobile app for one side or both, as well as the website.
• Integrations: automatic invoicing, logistics or tools sellers already use.

Examples at today’s prices

These amounts come from the same estimator our assistant uses, with today’s rates. Use them as an order of magnitude; describe your marketplace to the assistant to get a fixed price for yours.

Validate the business first, not the technology

The risk in a marketplace is almost never technical: it is getting sellers and buyers at the same time. That is why it is worth launching a first version with just enough for real transactions to happen in a specific niche (one city, one category) and measuring. Many marketplaces start with sellers onboarded by hand by the team and a small catalogue, and automate later what really repeats.

Questions worth answering before asking for a quote

• Who pays the commission: the buyer, the seller or both?
• How is what is sold delivered: shipping, in person, online?
• What happens if something goes wrong: cancellations, refunds, disputes?
• How will you get your first fifty sellers?
• What makes your platform indispensable compared with what people use today?