When I was younger, my parents were not the rolling around in money (and still aren't) but they are happy. I saw they were happy and realized a few things about how my dad did things on the farm as I grew up.
1. Know what you're paying for. Whenever my dad goes to Bomgaars, Wally parts, an auction, the sale barn, etc, etc, etc he literally looks the potential purchase over and compares it with the others. To him who gives a rat's can (that's my dad's saying) about more in the purchase (quantity), he wants it to last (quality). You wouldn't buy a sick cow, so why would you buy a flimsy plastic shovel to clear your sidewalk?
2. Do the math. When my dad and I went to the grocery store he always took out his phone (or used his head) to figure out which package of shredded cheese was cheaper, the 2 or 6 cups. He did the math with a bunch of food, I choose cheese because that was the first time I saw him do it. Let's say your cheese is the (made up) cost of 1.25 for 2 cups and 2.75 for 6 cups. If you divide those out, a 2 cup bag costs you a 0.625 per cup and a 6 cup bag costs you 0.4583 per cup. Which bag of cheese would you rather pay for to get more out of your money?
3. Make sure it'll be to good use. Don't buy things you will not need and use ever (also known as a lot), it is a waste of your money.