Hi again-
I'm not telling you to give up now, I'm telling you that providing sound directly and exclusively to bands that play in bars will not make you a living.
I don't know what mixerpersons make for 'band in a van' gigs these days, but it was about $75/night 20 years ago. I doubt that has changed. Indie band in a bus... that might get you $250/night or $1000/wk plus per diem. Not bad if you can do it 52 weeks a year, but unacceptable if you acquire a family that expects you to be home.
Here's the deal: You'll spend $20-40K building a bar band rig acceptable to the occasional "D" level national or regional act. You need to pay yourself back (with interest) for that investment as well as paying yourself to be the technician at the gig, AND you need to pay yourself for running the company, too. This is where most start ups fail. They don't factor in those costs when setting prices and work too cheap for too long, establishing a pricing precedent that is almost impossible to break out of. Trust me, I've done it myself and watched others do it, too. As a manager, it's my job to not have my employer take that track.
One needs business education as much or more as one needs advice about consoles and speakers. Develop a business plan. Seriously. That will be the litmus test that shows if you have profit or loss on your horizon.
Have fun, good luck.
Tim Mc