Comment by gjm11

I think these calculations are a bit bogus.

If you spend $35k on a nice computer, and then earn $35k from doing some work using it, that doesn't mean that buying the computer has paid for itself unless the computer is solely responsible for that income. It probably isn't.

It's not necessarily even true that after doing that work it's "paid for", in the sense that getting the $35k income means that you were able to afford the $35k computer: that only follows if you didn't need any of that income for other luxuries, such as food and shelter.

If you're earning $50/hour, 40hr/week then what you've done after 17.5 weeks is earned enough to buy that $35k computer. Assuming you don't need any of that money for anything else, like food and shelter.

If the fancy computer helps you get that income then of course it's perfectly legit to estimate how much difference it makes and decide it pays for itself, but it's not as simple as comparing the price of the computer with your total income.

Regardless of how much it contributes, if you have plenty of money then it's also perfectly legit to say "I can comfortably afford this and I want it so I'll but it" but, again, it's not as simple as comparing the price of the computer with your total income.