We've done some work for Abstracts USA (First Title Services) since the 1st of December.  Since they've had some bad reviews on paying their abstractors, we requested they provide a valid Credit Card to pay for the searches they request.  So far so good.  I have our accounting dept. run the CC prior to sending the search results back, and then send a copy of the sales receipt & CC transaction receipt back with the results.

We've been requesting CC info for the past 3 years on web requests, after getting stiffed a few times.  If they don't contact our accounting dept. with their info, then the request goes into the dead file.