Crayons
This one may be a bit random, but you should avoid buying off-brand crayons because you will find that they rarely work well. Their price is cheap but that’s because their quality is too. You may as well buy them at big-name stores where they will work better in the long term.
Jewelry
While cheap jewelry can be awesome, blue arms from a rusty bracelet are something we all like to avoid. Dollar store jewelry is simply not worth buying, even if it is extremely cheap. Take your money and buy yourself something nice instead of something that will break or damage your skin.