@Ty Carl
I'm also a high schooler and I've been researching starting a vending machine business for a while!
I first looked into it for passive income but from what I've found it's a business as any other. It may be passive income in the future but at the beginning you are just self employed.
From what I've found, some locations will want you to give them part of your gross revenue. This is something you could do to make a vending machine offer look better but it is not required to offer this in order to get a location.
In my area there is always decent used vending machines for a little under 1000 and some even have a warranty. You will want to have a location ready when you buy a machine because it costs about $100 to have someone move a machine.
I've been struggling to seem credible (since I am a teenager) to businesses in my area so im looking into purchasing 2 vending machines with location. Make sure to talk to everyone you know about if they or anyone they know have a need for a vending machine. If you find someone that one it should be a ton easier to set something up.
Let me know if it's something you are going to pursue because would love to hear updates on it.