I would be concerned about charging for the seminar. The only reason
that I would say this is that seminars are really more of an
introduction to your company and less about the content delivery. If
for example, you were holding a 3 day workshop on a particular topic
(that you were a well known expert at), then charging would be
expected. But if you are trying to filter out the "real" prospects, I
think that is best left to filtering you invitation list. It is for
the advisor to get the attendees interested in their services and this
should be done by positioning your company's services against its
competition.