In a typical project, resources are assigned to subtasks, not summary tasks. However, there may be some situations where assigning a resource to a summary task is appropriate. If you decide to assign a resource to a summary task, keep in mind you might not be able to resolve overallocations.
Assign people to work a summary tasks:
In the Gantt Chart, go to the Resource Names column.
Click the arrow and pick the people to work on the task.
If you don’t see the name of the person you want to assign, enter a new name.
One case when summary assignments can be used is a project where the project manager is responsible for the whole project.
On Resource Sheet view set – std rate for Project Manager resource
To check cost for all project just insert Cost column