Scenario: This organization has 5000 employees who are in several locations within the continental United States. Most of the company's computers are Windows 7 PCs/laptops. The organization has no special PC needs for employees with specialized skills, such as CAD operators and engineers. Employees in this organization rely heavily on the PCs they use to complete day-to-day tasks.

Based on the above scenario, develop a comprehensive plan for keeping PCs upgraded and functional through a proper hardware/software lifecycle.