Which pricing and billing method involves charging for services based on a predetermined or published price list?

The pricing and billing method that involves charging for services based on a predetermined or published price list is called the unit pricing method. This approach provides customers with clear expectations regarding costs, as it defines the price for specific units of work or service.

Unit pricing simplifies the billing process, as each component or service is priced individually according to the established price list, making it easier for both clients and service providers to understand and agree on costs before the services are performed. This method is often preferred in commercial settings where transparency and budget management are critical, as it allows for straightforward calculations based on the quantity of work done.

In contrast, other methods like the fixed price method involve setting a total cost for a project regardless of the actual time or materials used, while cost-plus pricing incorporates actual costs plus a markup, and the time and materials method is billed based on the actual time and materials consumed during the service.