An SAP Business Object in Avantra corresponds to SAP Business Objects BI Installation. It must be linked to a standalone Database in Avantra which is set up to monitor the CMS database.
A Business Service is a cross-system (and even a cross-customer) Composite Check. In other words, while input checks of a Composite Check must be executed on a system for which the Composite Check is defined, a Business Service can have arbitrary input checks.
And although every Business Service is “owned” by a customer, it may have input checks from other customers as well. Input checks for a Business Service can be a Built-in Check, a Custom Check, a Composite Check, a System Status, or another Business Service. Business Services also record Availability Data.
An example for a Business Service would be to correlate all SystemAlive Checks of all productive SAP Systems. A Business Service is a Managed Object as well as a Check, so you can apply Maintenance Windows to it, for example. And, of course, a Business Service has a Check Status.