It seems like there are some folks out there that think they can get a great logo for $50.
As a freelancer you have an idea about what your time is worth. If it's worth $50 an hour that means that your client wants you to work 1/2 an hour on their logo for concepts, then 15 minutes to take care of their feedback and then 15 minutes to finalize the art in the various formats they will need.
Now, I will admit that I'm fast and creative... but there is no way that I can come up with a world class logo in less than an hour.
Bottom line... you want to work with clients that are serious about succeeding. Try to educate them about how important their logo is. Explain to them that they will be spending a lot more money in the future plastering their logo everywhere and that in the long run a poor logo will be more expensive in the long run.