Aggregating Multiple COTS Databases into a Data Warehouse or similar for Reporting
It appears that you just want a copy of all your databases centrally located, which could then be used to run the same report for different regions, just by changing the datasource?  

You could acheive this with a single Server and a single instance. 

While I wouldn't call this a data warehouse (per se), but it might be the simplest solution to solve your requirements.

With this approach you would end up with 42 databases on your instance and you could name them anything thing you like, but I would suggest including the source location in the name of the database

- for example
   [Source Server].SourceDB    --&gt;      [Dest Server].DestDB
  [Sydney.xyz.com].Database1   --&gt;  [Central.xyz.com].Sydney_Database1
  [Sydney.xyz.com].Database2   --&gt;  [Central.xyz.com].Sydney_Database2
[Brisbane.xyz.com].Database1   --&gt;  [Central.xyz.com].Brisbane_Database1
[Brisbane.xyz.com].Database2   --&gt;  [Central.xyz.com].Brisbane_Database2
etc...


You could achieve this via


Replication ,or
Log Shipping


Both of these solutions are relatively simple (assuming you have network access between all your nodes), and replication you only need to replicate speific objects (tables, procs etc) that you use in your reports (whereas log shipping will be the whole database), but replication can be problematic to troubleshoot.