I understand as well, as to what you may have paid for it, what the restoration costs..etc....
It would be like saying a Chrysler 1986 K car in rough shape goes for 100, but the cost to restore it is 4000, so then the value of the car MUST be at least 4100 after restoration.
All that car would be is a 100 car with a nice restoration... then the market dictates what the value is. And with a 1986 K car, such as a Vendo 83, there is no market for it.
Not to say like others have said here that there isn't a buyer out there that just HAS to have this machine, as is willing to pay the cost of resto etc.... but at this time they are hard to come by.
Well, you can't take the cost of a resto, which most of it is labor, and add that to the "value" of the machine / car. Like cars, there are collectable vending machines, and no so collectable machines. Getting one that you like is the key, and if you like it don't worry about what it's value is.
If you're asking the value because you want to flip a machine like this.... well, good luck with that. Getting a 83 for free is still tough to make a profit to flip it once you figure your gas, time maybe a trailer just to get the machine.
Welcome to the board though!