Maybe wrong but I think in the case of a franchise you don't own the work, you get a royalty/fee for the work they do, the idea is brand awareness you provide everything needed such as leads, tech support, training etc.. How much would depend on what your charging, they have a can with your branding on, and hopefully they do a good job and grow an Independant biz.
Renting means the work is always yours to take away as and when you like (within reason)
Darran