The difference between Amazon's single site and multi-site is as follows:

1. Operation strategy: The operation strategy of a single site is relatively simple, and you only need to focus on the sales of one site. The operation strategy of a multi-site is much more complicated, and you need to focus on the sales of each site and formulate different operation strategies for different sites.

2. Logistics and inventory management: Single-site sellers only need to manage one warehouse, while multi-site sellers need to manage multiple warehouses. This increases the complexity of logistics and inventory management, but also provides sellers with more sales opportunities.

3. Market coverage: Multi-site operations can cover a wider market, including consumers in different countries and regions. This helps increase sales and market share. The market coverage of single-site operations is relatively small, but it is easier to cultivate.

4. Competitive environment: In multi-site operations, sellers need to face competitors from different countries and regions. This increases the intensity of market competition. In single-site operations, sellers only need to focus on competitors in one site, which is relatively easier to formulate and implement competitive strategies.

5. Language and cultural differences: Multi-site operations need to face the language and cultural differences of different countries and regions. This requires sellers to have cross-cultural communication skills and in-depth understanding of the local market. Single-site operations do not need to pay attention to these issues and can focus more on product and market research.

6. Legal and compliance requirements: Different countries and regions have different legal and compliance requirements for e-commerce. Multi-site operations require understanding and compliance with the laws and regulations of different countries and regions, which increases the difficulty of compliance. Single-site operations only need to focus on the laws and regulations of one country and region.

In short, there are obvious differences between Amazon single-site and multi-site in terms of operational strategies, logistics and inventory management, market coverage, competitive environment, language and cultural differences, and legal and compliance requirements. Which method to choose depends on the seller's specific situation and strategic goals.