Generate a full detail guide on supply chain management for small businesses. The guide should simplify complex operational concepts. It must include detailed sections on: 1. Sourcing and Supplier Vetting: How to find and build relationships with reliable suppliers. 2. Inventory Management: An explanation of key concepts like safety stock, reorder points, and inventory turnover. 3. Logistics and Fulfillment: A comparison of in-house vs. third-party logistics (3PL). 4. A glossary of common supply chain terms. Please include a disclaimer about the complexity of international supply chains.