I've taken over a project (with no documentation ;o) which will use WHMCS as the central ordering and invoicing system for a subscriptions based business. I'm using the API to add clients/orders/products etc and so far that's all fine.
My main area of uncertainty is around the actual payments. We are using Sagepay direct as our gateway only we don't want to store any credit cards in WHMCS.
Am I right in thinking that I will have to make the transactions with Sagepay using their API myself and then use API: Add Invoice Payment to update the invoices within WHMCS.
My question is, following on from the original payment, we want our clients to be billed in a recurring fashion. Is there a way I can get WHMCS to do this just using the TX Authenticate from the original Sagepay authorisation?