1. Go to Contracts - Contracts.
2. Click on the Contract you would like to add a 'Custom Rate' to.
3. Go to the Details tab.
4. Scroll down to the Rates area.
5. Here you can add the Rates by filling out the data that applies to your contract.
6. You can also add an additional 'Custom Rates' by clicking on '+ Add Custom Rate' button.
7. Here you can fill out the custom rate information.
8. Click 'Save'.