Does anyone have experience with multi-unit franchise valuation?

Does anyone have experience with multi-unit franchise valuation for businesses that include both operating stores and territory rights for undeveloped areas?

On the one hand, a franchise provides certain strengths as far as SOPs, marketing, etc.; on the other, it seems ill-suited for a PE platform because it can't be developed into its own brand and wouldn't work as an add-on for an existing platform. Similarly, I don't see why a buyer would pay a premium for territory rights versus what the franchisor is selling new territories for, unless those undeveloped territories have particular synergies given the owner's existing footprint of stores.

Any insights would be appreciated.