Thanks for visiting the Community today, @Hiroki. You can enable to Advanced Pricing in the Sales and Customers Preferences. Then, set up the Price Levels so you can automatically change prices based on customer type. 

With this being set-up, you can do the following: 

• Change the price of all items sold to customers assigned a customer type in the customer center.
• Define specific item prices to charge customers assigned to a customer type.

Here's how to enable Advance Pricing: 

1. Go to Edit, then select Preferences.
2. On the left panel, click Sales & Customers.
3. Select the Company Preference tab, and under the Custom Pricing section, click the Get started with Advanced Pricing link.
4. Follow the on-screen instructions.
5. Click OK once done.

To create a Price Level, here's how: 

1. Go to the Lists menu, then select Price Level List.
2. Select Price Level at the bottom, then choose New.
3. Enter a name for the price level on the Price Level Name field, then click OK.

For additional insights about Price Rules in QuickBooks Desktop, read through this article: Use Advanced Pricing.

for future reference, you can browse our QuickBooks Articles hub to search for some relevant topics, tips, and some steps for your day-to-day QuickBooks tasks.  

Feel free to comment below if you have any other questions. Wishing you continued business success.