uStar is included in UPA (but HomeZon and TraffZon are not). If you purchase HomeZon, you now have an additional tool to use uStar with. RepZon and uStar are the same thing.
You can bill the client through Umbrella's billing system, or charge yourself the wholesale price and bill your client using your own processing service (paypal/stripe etc.)
Please see this link to learn more about uStar: https://www.umbrellaus.com/copy-of-ueverywhere and contact the support from the above link for any further questions regarding the program
After onboarding, the service will begin in a few days. You just need to schedule a call with the client and Broadly in which they explain and implement the service for each client. It would be best if you are also present on that call. From that ...