How does a cabbie buy his own cab, under the huge national company, and

[Old Gamer 56]

pay for dispatch service? I have been doing the thing where you lease the cab for 12 hours or a week. I was told that a few cabbies had bought their own cabs, but it was still the nation wide company. They own their own taxi cars, and pay the big national company, or this local branch for dispatch service. I was told they pay $500 weekly for dispatch service, but that sure sounds high. Does that sound right? If not, roughly what would one pay for this dispatch service?
If some one out there knows the taxi business, and can shed some light on this for me, I would appreciate it. Thanks.