Asklemmy

Soap of any kind. It’s fine if you want a certain smell, but at the end of the day it all works the same. Goes for hand soap, shampoo, detergent, body wash, etc.

Most things. Clothes, cookware, phones, TV's, etc.

I would say only spend money to buy things you're passionate about. I love cooking and have spent some money on quality ingredients. Buy good spices and pans, erc. But I hardly spend money on clothing or vehicles or phones, etc.

Free computer operating systems are great these days.

I regularly spend hours designing electronics to be cheaper. Not worse -- just cheaper. Electronic components sometimes vary in price by two orders of magnitude for the same performance, so it's worth cramming datasheets in your head as a professional or hobbyist.

For tools, I've found good midrange Chinese brands, and stuck to them. I could never afford things like Tektronix and so on.

I don't strictly require clothing to be cheap, but I do require it to be fungible -- this works out similarly though. When I find something that's good value for money and looks good, I buy a bunch and rotate them. That way I don't have to think about what to wear, and it always looks decent.

I also prefer cheap laptops. I don't need a supercomputer to work. When I do need a supercomputer, I rent one from google cloud for a few dollars an hour.

Mascara. I’ve spent $20+ dollars a few times for some high-end Sephora brands, but I’ve never thought they were any better than the $8 Maybelline I can get at the grocery store.

From my experience so far most things in life can be found cheap, moderate price and expensively priced. However there’s a point of diminishing returns on your investment ie after that point you could spend loads for marginal gains. Find this point see where on the graph you can afford it.