All of the above.  No one wants to pay a fee to talk about what you can do for them.  To most people, a consultation is a sales call, from either perspective.  All services and products should be guaranteed.  Why would I purchase a product or service that will not fill my needs, or live up to it's  promise?  It's a simplistic answer, I know.  But it's a basic principal that works, and IMO should be promoted by every business.