Out of curiosity, how many hours do you need to fly left seat for a charter op in Canada (or any equivalent of our Part 135)?
The short answer is "1500 total time." A captain need to hold an airline transport licence, and the minimum time to hold one of those is 1500 hours. A considerable amount of multi-engine time and multi-PIC is usually required, so it's the rare pilot who manages to make the numbers line up that soon. Here are numbers from some recent job ads that have appeared on an online job site:
Navajo captain charter/cargo: 1500 hrs TT, 500 hrs Multi, 100 hrs Multi/PIC
King Air 100 captain sched/charter, remote base: ATPL, 250 multi-turbine
Jetstream 31 captain: 2500 Total Time, 1500 Multi, ATPL
It's either the multi time or the PIC time that holds a person up. The only way to get the multi time so soon is to get hired on as an FO while you're still wet behind the ears. Then you're stuck in the right seat for three years, at which point you might quit, or your employer even kicks you out to go and build PIC time. There's an employer recently who was hiring a Metro FO, looking for an ATPL, 1800 total time, and 800 turbine PIC. Someone even commented on the job bulletin board site, on the unliklihood of that combination.
I would recommend that a pilot starting out do his or her level best to get a first job with an operator who has a mixed fleet of say, Cessna singles, light twins like Piper Seneca or Aztec, flown single pilot, and multi-turbine two-crew. By all means take a first job flying anything but don't get so focused on it that you don't quickly hop to an operator who can give you that advancement path. You build PIC time in the light singles, until you meet total time requirement for the two-crew operation. You prove sensible there and when you have the multi time to be insured PIC in the piston twin. You can earn your ATPL that way, and eventually you PPC left seat in the turbine machine. All without the pain of more job hunting. And I left out the part about working for two years slinging bags.