I have see the "brothers" follow two basic tracks in business. The first being multi level marketing. This almost always ends in disaster. The business continues to until the marketers reach their credit limit on the credit cards when they buy their inventory.
The other being some sort of cleaning or other service related business. A person can eke out a living doing this. But I have never seen anyone get rich. I always hear about those that get rich with a cleaning business, but never met any of these people. Nor have I reviewed their financial statements.
We had an elder with a TrimLine franchise. I understand that ended in disaster. There were a number of brothers involved in the carpet cleaning business. I forget the name, but with all story's of wealth, I never saw any of it. Just a lot of very hard work with little payback.
With my financial background as a CPA, an brother asked me to review his books in his cleaning business. He was convinced that he was making a fortune, but from what I saw, he was barely making enough to pay off the capital investments of the machines.
Starting and maintaining a small business is very hard work. It requires skills beyond the scope of most people. I admire those who succeed. Unfortunately, the religion creates one additional barrier to success.