Hello,
Replacing the brake fluid, or flushing the brakes system, is a job that can be done by anyone with some mechanical ability and the proper tools. However, it's not a job I would recommend unless you have some good guidance from someone who fully understands the hydraulic braking system. The main idea is that you want to push the old fluid out and replace with new fluid, leaving no air bubbles in the system. Failure to do this right can cause parts (master cylinder) or brake system failure.
Shops generally don't charge too much to do this, so I think it's worth having it done professionally. Just make sure they use a tool that flushed the entire brake hydraulic system.
If you wish to do it yourself, I suggest getting an brake bleeding/flush tool and perform a search online for "How to flush brake system" and you'll see pictures, maybe even video on how to do this job. I do not suggest using the brake master cylinder to push the old fluid out of the system, this can damage it.
Good luck!
Thank you for your thoughtful reply. After watching at least a dozen videos, I understand what you mean about not using the master cylinder to push the old fluid out. I recall being a part of this procedure being performed many years ago in my garage and helping out, i.e. being the 2nd person to push the pedal. Will further consult with my brother, who is a master mechanic but lives 2500 miles away. I am confident that I can get the job done property and completely with proper supervision the first time- that's what friends and family are for. I have learned that there are many jobs big and small that can personally be handled with the proper guidance and research without having to pay a professional every time. It would normally cost me @ $100 for this procedure, necessary as it is. Doing it myself means a couple extra trips to the lake on the jet ski. Therefore, this is a new one on my list. Thanks.