1.

Log in to your eBay account and go to "Seller Backstage".

2.

Select "List" in the left navigation bar.

3.

Select the product that needs to be limited, and find the "Item Details" tab on the "List" page.

4.

Find the "Purchase Restrictions" section below the tab and check the "Enable Purchase Restrictions" option.

5.

Select the "Maximum number of purchases per buyer" option and set the number to 1.

6.

Save and publish the product. In this way, you have successfully set a limit of one item per person for the product. This will ensure that each buyer can only purchase one item to avoid over-buying and excessive bidding.