You have 2 options: Assign the desired rate to your users at the project level, or at the task level.
What this means is that in the Enterprise Admin zone you need to create an external billing rate reflective of the discount (or multiple rates if there are several). Once you have this rate category (call it "Bulk Customer Discount" if you will) then you move on to the project.
If you apply it to all users involved with that project:
1. Go into the project and list of members, then edit each member.
2. Assign the Bulk Customer Discount rate to those members. This will supercede that user's Enterprise Rate just for this project.
If some tasks are discounted and some are not, then you would want to assign the rate at the task level by editing each discounted task and setting the rate to Bulk Customer Discount rate. The Task rate supercedes the Assignee rate. If there is no Task rate, then the Assignees Project Rate takes precedent. If there is no Assignee Project Rate then the Assignee's Enterprise Rate takes precedent.
If you do not see any external/internal rates in your project it is because it is an permission that needs to be set for the role you play in the project. In the admin zone select User Settings, then select Project Roles and pick the appropriate project type and role, and select "Can View Billable Rates" etc...
Steve Thompson | Solutions Consultant
Daptiv