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Discount percentage based promotions are defined using just the Finance Promotion record, and are for percentage based promotions. E.g. xx% off.
You can target then enable specific services or schools of services by using the Finance Promotion Relationship links (see below).
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Create a new Finance Promotion
Navigate via System Objects to Finance Promotions
New
Enter the discount
Enter the discount amount or discount %
Enter the Valid Type - by Booking Date of Start Date
Enter the Valid from/to dates
Create (assign) the Finance Promo Relationships
These control which Services (or School) are eligiable eligible for the discount
Test
Setup a test student (if you don’t have one already)
Test your new Promo Code
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