Do you value an ounce of gold based on the hours that went into mining and refining it, or a Picasso based on the quantity of paint that went into it?

It's worth the value the buyer can get out of it, not what you put into it. Typically that's the expected values of future cash flows, discounted to the present using an appropriate risk-adjusted discount rate.

You can estimate how much cash it might generate under various scenarios, and estimate the probability of those scenarios transpiring, to come up with a value.

If you can persuade someone there is future cash flow, you can sell it. Otherwise, you can get a dime for it if you throw in a couple of nickels.

(disregarding strategic, humanitarian reasons to buy it, or the possibility someone is planning to spend X hours to build the exact same thing.)