Clients want free work and ideas. As a creative professional you should just say NO!
About a year ago I was asked to bid on creating the design work for a magazine for a small liberal arts college. … We really like your work, they say, but we’d like to see a 4-page page mock up of what our magazine would look like if you redesigned it. At this point, my spidey sense is tingling and I politely agree to the request as long as they reimburse me for my time. We consider this an “audition”, I am told, and they will not pay for my services. This is spec work. Thanks, but no thanks, was my reply.
For the rest, go to Spec Work Hurts Graphic Designers