You can explore the Service Plan Items settings in the Control Panel to define the Service Plan items used in the service plan.

A Service Plan item defines the type of service, its billing frequency, and the price for providing it.

Service Plan items determine the price of the service plan and are intended to be displayed in the Plan Details section of the Service Plan report.

To access the Service Plan Items settings, click the following icon.

This will open the following form.

You can add as many service plan items as you would like to.

To add a new item:

1/ Click New.

2/ Add a name for the item.

3/ Add a description or use snippets for the description.

You have the option to change the case of the description and a Spell Check to fix spelling errors.

You should add a comprehensive description of the item.

4/ In the Frequency section, select the billing frequency of the item.

You can choose One Time, Weekly, Biweekly (once every two weeks), Monthly, Bimonthly (once every two months), Quarterly, Semiannually, or Annually.

5/ In the Price section, do the following:

a/ Choose Standard to set a fixed price for the service plan item.

b/ Choose Calculated to set the price based on the items in the project.

c/ Click Compute and choose or set the following:

The source you wish to use for the service plan item price calculation.

If the field applies to all project items or just those added to your service plan.

The operation for your calculation.

The value to determine the service plan item price.

6/ Select whether the plan item is taxable.

7/ Click Save.

You will add service plan items to service plans in the Service Plan Explorer. After adding a service plan item to a plan, you can edit its name, description, and every other detail.

You also have the option to set the start date for every item added to the plan.

Check out this article for more details.