Let me throw my 2 cents in. I owned and operated a 100 series for about 8 years, flew single pilot until the last two under 135. The insurance company dictated two pilots the last two years, and both pilots needed Simcom or something annually.
You didn't need 2 pilots per the FAR's,,,UNLESS the autopilot was inop for IFR operations. But then,, the friendlies really got rid of that loophole by mandating a cockpit voice recorder for any turbine powered six seater or more if there was no/inop autopilot. And, very few (including me) were willing to shell out for a CVR for an older King Air.
History lesson over.
Hung