Your account will be charged for setting a task and the number of results you will get in the items array. The cost can be calculated on the Pricing page.
Setting Apple App List Tasks
This endpoint will provide you with a list of mobile applications published in the top app charts on the App Store platform. The returned results are specific to the app collection as well as the language and location parameters.
Your account will be charged for every 100 results returned, e.g., if you specify "depth": 101, you will be charged as per 200 results.