Tracking Revenue that comes in without an Opportunity

Hi everyone,

We are just getting started in tracking Opportunities through Marketo.

How should we handle Revenue that comes in without any previous Opportunity created? Our concern is that if there was never any Opportunity, the money from that sale won't show up in our analytics.

(Before you ask, yes, orders come in for our software without any warning. The salesrep never created an Opp because they didn't know the customer would buy. I guess it's a good problem to have.)

We've thought of two possibilities:

1. Have the salesrep create an Opp, and then create the order from there. That way we'll get the tracking info in the Opp, and when the Opp is marked as Won, it will update the lead to Customer status in our Revenue Cycle Model.
2. Use a different kind of trigger from the order, to send the info to Marketo and update the lead to "Customer" status. Not sure if this is possible.

Do other companies face this, and how do you deal with it?

Thanks!