What is the best practice to prevent a user from discounting a specific Product Type?

Attribute ''memory '' has a ''user Selection w/Quantity inputs for each Attribute value'' Attribute type.
Which Display type should you use to allow the input of quantities in the configurator?

Which tag allows the use of any available element in formulas, product configuration, rules, approvals documents generation, etc,?

In a configurable product, pricing is defined both in the product Base price, and also in the price field of some user selected Attribute values. If the user selects an attributes value that has a price, how is the resulting product item price calculated?

What is the right tag to use for the calculation formula of a Quote Item Custom Field if its value depends on a product attribute value?