I'm coming in here behind the ball, but here is my take on it:
I've been homebrewing for 3 years, and have been rather successful at it. Numerous gold medals, a silver, and more HMs than I could count. I've had the "Your beer is great! When do you open your brewery?" question many times. So I contacted a few wealthy friends about the idea, and one of them was very enthusiastic about it. Well, until it came time to actually put down some money for it, then he was strangely absent. Needless to say, I was pretty discouraged. I had spent a LOT of time, researching, meeting with other brewers, talking to city officials, etc...
So I decided to stick with just homebrewing.
But I never gave up my belief in, and desire for, becoming a pro brewer.
I was lucky enough to meet with a local pro brewer through my club, and he mentioned that they needed an assistant. Who do you think was jumping up and down, shouting "Me! Me! Me!"? He then contacted me, after talking to several of the officers of the club, and offered me the job. It was a tough decision, to step away from a decent paying job, and start at the bottom in a new profession. But I did it, and have been the happiest I've ever been.
It is a lot of time spent cleaning. And cleaning. And cleaning. And cleaning... You get the point. It is many many hours in a hot and humid environment. Even with boots on, my feet are constantly wet. Grain get very freaking heavy, after you've lifted 10,000 lbs worth to sort and stack in the grain room. It is very dusty and dirty, after milling a batch. Then cleaning the mash tun, when 1000 lbs of grain becomes almost 2000 lbs of wet, hot grain.
But you know what? Best decision of my life. I couldn't be happier, working a hard, labor intensive job for a smaller paycheck. So you want to be a brewer? Better know what you really want. If you want all this, then good luck. A lot of people think they can handle this, but don't know what they are getting into. The head brewer where I work told me they have fired or let go of many assistants who thought it was all fun and drinking beer.
If you want to open your own brewery, better have a lot of capital to back you up. And be prepared to work harder than you ever have. If you truly love it, it won't be work.
I love my job, and go home more tired and sore, but ultimately more satisfied, than I ever have.