This is a great info,
I have some questions, adding to your info can help to make a business plan:
Which is an attractive payback time for a machine?
How do you work with loans for machines? If you use them, do you extend your Payback time per machine as long as the loan is?
What is your threshold of monthly payment or machine purchase value?
How do you choose to get a new vending machine instead an used or refurbished?
How do you set prices per location based in product costs, number and type of potential customers, machine investment? To fit with your expected profit