First of all, we need to know the economic level and consumption ability of this product between different regions. For example, clothing, if China is headquartered in Shanghai, and Shanghai has strong consumption capacity for this product, then the discount rate will be more. If clothes are sold in other cities, the discount will be less because of the limited consumption level and the logistics costs such as transportation and warehousing.

Then, we need to know whether the sellers of the same product are sold by the same company. For example, if the employees of multinational companies are well paid and all services are standard, then the discount on products will be less. If the product is sold to an agent, the price of the product cannot be unified because the agent is responsible for its own profits and losses and pursues profits.

Finally, what we need to know is whether the customs affairs in different regions are consistent, and different countries and regions have barriers and duty-free for all products. For example, importing foreign cars into China and Japan are two different things. China adopted tariff barriers to protect local products, which led to product prices rising. Japanese cars are very developed, and they are not afraid of the impact of other countries on the local auto market. If imported cars can be imported as ordinary products, the tariff will be much lower and the price of cars will be lower.

Of course, there are more objective and subjective reasons.