It should be noted that sociopath is not a formally defined psychological term currently in use. The modern terms closest to the term are conditions like Antisocial personality disorder and Conduct disorder. And those conditions are associated with lower, not higher, IQs. The same is the case for serial killers (http://maamodt.asp.radford.edu/Serial%20Killer%20Information... and https://www.fbi.gov/stats-services/publications/serial-murde...). One of the primary symptoms of those conditions is poor impulse control and planning ability.

I've never seen the claim that serial killers tend to be small business owners, do you have a source for that?