You can make a very very comfortable and lucrative living if you got the drive and the skills.
However don't plan on having nights and weekends off, if freelance is the way you go....definately alot more work than showing up to a job everyday, and collecting a check.....but all that more rewarding.
It takes alot of self promoting, and you have to be able to sell yourself.
since your best chance of building business, will be getting your customers to return for more, and actually have them recommend you to their colleagues....you have to give 200% all the time.....or they will find someone who does.
Always remember to charge what your time is worth, and pay your taxes....otherwise you'll end up in trouble sooner or later.