Episode 14 What It Takes to Build a Marketplace Ft. Mark Hill of MyCardPost

Released: August 12, 2025 | Duration: 39:00

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About This Episode

This episode features Mark Hill, founder and CEO of MyCardPost, discussing one of the most daunting undertakings in any industry: building a marketplace from scratch. Mark shares the origin story of MyCardPost, a subscription-based platform with no seller fees that has grown to 16,000 users and over $4 million in total deals completed. The conversation explores what it takes to start, build, and scale a marketplace in the sports card world where traditional platforms charge heavy transaction fees and limit how collectors can interact.

MyCardPost operates on a fundamentally different model than eBay or other established marketplaces. Instead of taking a percentage of every sale, the platform charges a small fixed monthly subscription starting at only $9 per month. This allows unlimited deals and trades within the community without the burden of high seller fees or buyer premiums. The platform is built to replicate the experience of a physical card show online, with no limitations to deal-making options. Whether buying, selling, or trading, collectors have full flexibility in how they structure transactions.

The episode dives into the challenges of building trust in a space where collectors have been burned by high fees, rigid restrictions, and platforms that prioritize profit extraction over community building. Mark discusses how MyCardPost has grown through word-of-mouth and community endorsement rather than heavy marketing spend. The conversation covers the technical, financial, and emotional challenges of bootstrapping a marketplace, why protecting collectors is not only possible but necessary, and what it means to build a platform designed for collectors, not off collectors.

Topics Covered

  • What it takes to build a marketplace in the sports card industry from scratch
  • The origin story of MyCardPost and why Mark Hill decided to create an alternative to traditional platforms
  • How MyCardPost operates on a subscription model with no seller fees, starting at $9 per month
  • The difference between transaction fee models and subscription models for marketplace sustainability
  • Growing to 16,000 users and over $4 million in total deals completed through organic growth
  • Why trust is hard to build in the sports card space after collectors have been burned by high fees
  • How MyCardPost replicates the physical card show experience online with unlimited deal-making flexibility
  • The platform’s features: marketplace listings, direct trading options, a Feed for posting interests, and a Leaderboard for top traders
  • Why transparency matters: showing community size, total deal value, and fees saved compared to competitors
  • The technical challenges of building a marketplace that supports buying, selling, and trading in one platform
  • The emotional and financial challenges of bootstrapping a business in the sports card space
  • How to build a platform designed for collectors, not off collectors
  • Why protecting collectors from predatory fee structures is both possible and necessary
  • The role of community endorsement and word-of-mouth in growing a marketplace
  • How subscription models align incentives between the platform and users versus transaction fee models
  • The future of sports card marketplaces and what collectors want from platforms

Full Transcript Summary

The Origin Story of MyCardPost

Mark Hill founded MyCardPost to solve longstanding hobby frustrations including high fees, rigid restrictions, and the lack of a trusted marketplace for flexible collector-to-collector deals online. As a lifelong collector, Mark experienced firsthand the pain points of traditional marketplaces and decided to build a platform that aligned with collector values rather than extracting maximum fees from every transaction. The question he kept coming back to was simple: why does every marketplace take a cut of every deal when the platform’s value should come from connecting people, not taxing them?

The answer he arrived at was that nobody had tried hard enough to prove the alternative could work. Building a marketplace is one of the hardest things you can do in any industry because you need both sides of the transaction to show up before either side sees value. Mark bootstrapped through that chicken-and-egg problem without venture capital, relying on the strength of the idea and the willingness of early adopters to take a chance on something different.

The Subscription Model vs Transaction Fees

MyCardPost operates on a small fixed monthly subscription model starting at only $9 per month. This replaces transaction fees entirely and allows for unlimited deals and trades within the community without the burden of high seller fees or buyer premiums. The subscription model aligns incentives between the platform and users in a way that transaction-based models structurally cannot.

When a platform takes a percentage of every sale, its incentive is to maximize transaction volume and average sale price. When a platform charges a flat subscription, its incentive is to make users happy enough to stay. Those are different incentive structures that lead to different design decisions, different feature priorities, and different relationships between the platform and its community. MyCardPost succeeds when collectors succeed, not by taking a cut of every transaction.

The economics are straightforward for sellers who move any meaningful volume. A single high-fee sale on a traditional platform can exceed an entire year of MyCardPost subscription costs. For collectors who trade frequently, the savings compound quickly.

Growth to 16,000 Users and $4 Million in Deals

MyCardPost has grown organically to 16,000 users with over $4 million in total deals completed. This growth came through word-of-mouth and community endorsement rather than heavy marketing spend. Collectors who experience the platform’s benefits become advocates, telling others at card shows, trade nights, and online communities. That organic growth pattern is slower than paid acquisition but produces a fundamentally different kind of user, one who is there because they believe in the platform rather than because they were targeted by an ad.

The $4 million in total deal value is a milestone that validates the subscription model’s viability. It demonstrates that collectors will transact at meaningful volumes on a platform that does not extract a percentage of every deal. The fee savings alone, compared to what those same transactions would have cost on traditional platforms, represent a significant transfer of value back to the collecting community.

Replicating the Physical Card Show Experience Online

The platform is built to replicate the experience of a physical card show online with no limitations to deal-making options. Whether buying, selling, or trading, collectors have full flexibility in how they structure transactions. This includes cash deals, card-for-card trades, bundled deals, and any combination that both parties agree to.

Traditional online marketplaces enforce rigid transaction structures because those structures are easier to tax. eBay needs a final sale price to calculate its fee. That requirement shapes everything about how deals happen on the platform and eliminates the flexibility that makes physical card shows work. At a show, two collectors can negotiate anything: partial trades with cash on top, multi-card swaps, future considerations. MyCardPost brings that flexibility online.

Platform Features: Feed, Leaderboard, and Transparency

MyCardPost includes a Feed where members can post trade interests or buying and selling interests, creating a community space beyond just marketplace listings. The Leaderboard shows top fee savers, top traders, and other community metrics, helping new members find active and trustworthy participants. The platform provides full transparency on community size, total deal value, and fees saved compared to traditional marketplaces.

Transparency is a deliberate design choice. Most platforms obscure their internal metrics because the numbers do not flatter the platform’s relationship with its users. MyCardPost publishes them because they do. When collectors can see exactly how much they have saved by transacting on a fee-free platform, the value proposition reinforces itself with every deal.

Members can also link other marketplaces, personal websites, and social media profiles, recognizing that collectors exist across multiple platforms and should not be forced to choose one.

The Challenges of Building a Marketplace

Building a marketplace is one of the most daunting undertakings in any industry. Mark discusses the technical challenges of creating a platform that supports multiple transaction types, the financial challenges of bootstrapping without venture capital, and the emotional challenges of building trust in a space where collectors have been burned before.

The chicken-and-egg problem is the defining challenge: buyers will not come without inventory, and sellers will not list without buyers. Every marketplace founder has to solve this, and the solution is almost always the same: do things that do not scale until you reach the tipping point where the marketplace sustains itself. For MyCardPost, that meant personal outreach, community building at physical events, and demonstrating the platform’s value one collector at a time until the network effects took hold.

The emotional dimension is real and underappreciated. Building something that serves a community means absorbing the community’s frustrations, expectations, and occasionally its skepticism. Mark’s commitment to building for collectors rather than off them has been the through line that sustained the project through the periods when the numbers were not yet encouraging.

Why Protecting Collectors Matters

Protecting collectors from predatory fee structures and rigid platform rules is not only possible but necessary for the long-term health of the hobby. MyCardPost demonstrates that a marketplace can be built on fairness, transparency, and community values while still being financially sustainable. The subscription model proves that aligning platform incentives with collector success creates a healthier ecosystem than transaction-based extraction models.

The future of sports card marketplaces depends on whether the hobby’s infrastructure serves the people who participate in it or extracts from them. MyCardPost represents a different vision for what that infrastructure can look like, prioritizing long-term hobby sustainability over short-term profit maximization.

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