I wish to develop a system which plugs in to WHMCS and uses Freshbooks for all billing function.
I want WHMCS when creating a new client, to poll Freshbooks to see whether that client already exists in freshbooks.
If not, WHMCS should create the client in Freshbooks.
When WHMCS needs to create an invoice, it should do so via freshbooks and send it out to the client. When the client pays in freshbooks (or is marked as having paid in freshbooks) then WHMCS should respond accordingly.
Essentially I need Freshbooks to handle all billing functionality of WHMCS.
OPTIONAL: Building an admin area dashboard widget for WHMCS to show outstanding payments in freshbooks, and most recent invoices, etc.