Best way to handle project or customer discount

Hi,

We have the requirement to give a customer a discount on our base service (T&M) prices. Either on project level or customer level.

What is the best way to do this?

I've found a condition called 'customer discount' but that not in the pricing profile. Can I just add it? Should a new condition be created if we want discounts by project?

Hope y'all can help.

regards,

Jeroen