Which document details the work to be done and the cost of performing it?

The correct answer is the contract, as it serves as a formal agreement that outlines the specific work to be performed as well as the associated costs for that work. A contract is essential in construction and project management because it clearly defines the obligations and expectations between the parties involved, typically the contractor and the client. By detailing the scope of work, timelines, payment schedules, and any conditions for changes, it provides a legal framework that protects all parties and helps ensure the project is completed as planned.

Blueprints serve as architectural drawings that illustrate the design and layout of the project but do not provide financial details or the cost of performing the work. A project schedule, on the other hand, lays out the timeline for when different phases of the project are to be completed but also lacks information about costs. A change order is a document used to modify the original contract, usually to address modifications in scope or cost after the contract has been signed, but it does not independently provide the original work details or pricing. Thus, the contract is the document that encapsulates both work requirements and costs comprehensively.