How to calculate a commercial lease buyout?

Out of Pocket Expenses during Construction Period:
Equipments purchased/leased (minus any re-sell value)
MISC items purchased (minus any re-sell value)
Construction labor cost
Insurance premium
Loans and interests, penalties,
Other professional services, attorney, Architect, accountants,
Township permits and licenses, inspections
Partners' time invested
Travel expenses
Cost of living for temp housing during the construction period
Employee/personnel hired

Projected loss from the time of closing to establish a new location:
Projected loss of business branding values
Projected monthly profits loss x number of months of interruption of business Employee termination fees and severance packages
Projected equipment depreciation
Projected loss of time for renovation
Any possible court judgments for early terminations of personnel and services

I am sorry it took so long to see and find your question. You posted this as a answer to a 3 year old question, so honestly you are lucky anyone even saw it.

First from whose side, remember the renter does not have to ever agree to the buyout, so it is not a set rule, the person who owns the lease will want to offer as little as possible, and the renter will either not want to at all, or get the most they can.