Woolf,
If you are flying Part 135 (on-demand commercial operations) the basic FAA flight time requirement is: (for one pilot crew) 1400 hours per year. There are some other calendar quarter limitations, but this is the "biggie".
If you're flying commercial ops not under Part 135 (external load, ag, cattle herding, etc...) - you're on your own.
We don't like workovers, SAS?
C Ya