By principle, I rarely venture into businesses that do not have a high profit margin; I’m talking at least 50% or more within 6 months to 1 year, depending on how big my investment is.
Whenever new business ideas are introduced to me, I make it clear that unless I can have a 100% profit margin within a reasonable period, I won’t get into that business.
I’ve been a commercial catfish farmer for over a year now, and it is one highly profitable business; having a 50% profit margin within a span of 6 months is normal, if you do things right, and having a profit margin of 150%+ within this same period is not unusual.