Something new just popped into my head. Here are my rules for building marketplaces. I'm sure there are more.

What would you add?

1. If you don't have unique supply, you may not have anything different to offer the world.

2. Your marketplace must solve a real consumer problem. Can you identify it in a way that is clear?

3. In some ways, marketplace is a race between supply and trust. Supply must always win by a hair if you are pushing the envelope.

4. If you don't obsess over your vendor experience, why should they pick up the phone when you call?

5. The simpler you make it to onboard, the higher up the vendor's roadmap you go. There is an opportunity cost formula in the head of every potential vendor you are targeting.

6. It will take much longer than you think to sign up your supply. For services with product-market fit, I always follow a standard 10-3-1 sales formula (qualified prospect conversation - proposal - signed deal). If you are just starting out, you need more than this because you are still figuring it out.