It is possible to report across multiple organisations in Wink Reports. If you contact support we can set up your organisations in a hierarchy such as this:
Each organisation can have it's own connectors, such as to Xero, or ServiceM8 or Unleashed (all of our connectors). Each organisation can also have it's own set of reports which only users to that organisation can see.
However if users are added to the Head Office organisation, they will be able to access the information from all organisations in the hierarchy underneath them.
It's also possible to build reports at the Head Office level which will consolidate and roll up all the data from the Subsidiaries. You can choose to do this in the designer under the Report section.
To use this functionality requires an Enterprise subscription, which is quoted.
For more info, please contact the support team to help with setting it up.