Key strategic relationships. This has emerged as perhaps the key competitive advantage and barrier to entry of e-marketplaces. Get the big players in the fold first, offering equity if necessary.

Inventory Counting 101: Your Simple Guide to Better Stock Management
Running an ecommerce business? Then you know inventory is everything. But here’s the question: do you actually know how much inventory you have right now? Many business owners think as long as they have enough products to sell, the exact count doesn’t matter. That’s a costly mistake. Accurate inventory counts