Tristan Pollock is an EIR and venture partner at 500 Startups who has invested in over 1,200 startups over the past 5 years. The document discusses growing marketplaces and provides tips for Storefront, an online marketplace that connects makers to short-term retail space. Key points discussed include differentiating a marketplace through supply and demand, understanding where customers hang out both online and offline, testing marketing channels through "smoke tests" before large investments, and scaling growth through tools like virtual assistants and social media automation.