Solar options (mind field)

Cganddg

In all of these comments you are expecting to get your money back, and most likely that will be the case. Plus some profit once they have paid for themselves!
However can you name many other commodities you buy that will not become worthless after a period due to aging.
Applying the logic of something paying for itself over any period would mean nothing is ever worth buying. 

How much payback do you get from buying a car, and when does that become profitable?