What's a good way of thinking of expenses?

For example, a pair of 24$ pants that last 4 months might be .75$ per day of use (if it’s durable and lasts 2 years, then it’s down to .125$ per day of use :D). Choose wisely, and you’re paying less than a dollar a day on clothes.

A 1000$ laptop that lasts 3 years? That’s about .9$ per day for your laptop xD.

(With the small problem that you have to make the investment/gamble all at once, etc :P)

Taking the reverse view, food is damn expensive (trumping cheap rent D’=). Just 5$ a day on food is already 5475$ for 3 years, 15$ a day would be 15425$. ‘Small’ differences in how much you spend make a fairly significant difference in the long run (depending on how poor you are :P)

Which just reminds me why it’s ‘so easy’ to get rich with economies of scale: a .01$ profit on 200 million sales already gives you 2 million. Differences customers won’t even care about, are a matter of millions in revenue (u_u).

So clearly time and scale of use have to be taken into account, not just the raw $$ amount. What else needs to be taken into account when thinking about expenses?