Intercompany transactions

Can I set up intercompany transactions. ie if company A is paying an invoice for telephone services that were provided to both company A and B, can I pay the invoice though company A but affect the general ledger of both companies, while at the same time setting up an intercompany payable/receivable between the 2 companies?

On a related note, if I create a new inventory item in company A, can company B see the item and stock it, sell it, etc