Yes we too have been getting requests for quotes from companies that never send us any orders.  I suspect they are either using our quote to talk down some other abstractor, or, from the look of the orders, they have already done everything they can online and just want us to fill in the gaps.  I am doing several things with these requests, such as telling them to refer to our fee schedule, maybe even ignoring the request.  But I like your idea of charging for the quote and putting the money against the search if you get it.  If you do this, I would suggest you ask them for a return email verifying that they will pay the quote fee if they don't send the order.   If all the abstractors instituted such a policy, I bet those pesky quote requests would slow down substantially.