I need to set prices for services on the Magento platform. There are a number of conditions: for example, a person must choose the quantity of goods, depending on this figure the discount percentage will be calculated; in addition, there is a limit on the number of selected products, - if there are more than two hundred, then the user should see a message on the "Contact us" screen.
I understand that the platform has standard pricing methods. How can they be changed? Or is it possible to implement this with standard Magento tools?