Paying money to cash a check: If someone writes you a check, deposit it at your bank, and it will be "cashed" for free. Don't have a bank account? GET ONE. Or go to your local credit union. Alternately, go to the bank that issued the check and ask to cash it. You will need ID, preferably two forms. But its FREE and if you are poor, you can't afford to be paying people for money.
Pay Day Loans: Paying 30% interest so you can have money today, instead of a week from now makes no sense. Once you sign the papers on the PayDay loan, you will end up bankrupt. It is like slow-motion suicide. One payday loan leads to another, until you spend thousands of dollars in interest trying to pay off a $500 loan. If you are even contemplating a PayDay loan, use this as a wake-up call to reorganize your finances. If you are "running out of money" before PayDay, chances are, it is because you are spending it on things you don't need.
Paying ATM Fees: Using a "foreign" ATM and paying $2 to $5 in ATM fees makes no sense whatsoever, even in an "emergency" (most "emergencies" end up being anything but that, and most are just a result of poor planning). Even if it means walking a few blocks - or driving a few miles - to your own bank, it is worth saving the dollars.
High-Interest Rate Credit Cards: You can get a credit card today with a rate below 10%. Paying high rates (and some cards go to well over 50% nowadays) makes no sense at all. You will end up paying TWICE for each thing you buy. And chances are, most of the stuff you buy isn't stuff you needed. Get a debit card instead, or pay cash. It's a lot cheaper and you'll stay out of credit card debt, which is like a bear trap for the unwary.
Money Orders: Many poor people end up using money orders, which can cost a dollar or more apiece. Imagine, if every time you wrote a check, you had to pay a dollar! You'd get so upset, you'd burn down the bank! But poor folks think nothing of this. Most do this because they are afraid of banks, or have been turned away from banks because of staggeringly poor credit.
Rent to Own Furniture: Paying 2-3 times the value of an object, just so you can have it "today" and pay over time makes no sense at all. Yes, you need furniture, eventually. No, you don't have to have it "right away". I've slept on the floor in a sleeping bag while saving up to buy a bed, and so can you. Leaning to live without is hard, but it is far more profitable in the long run.
Consumer Financing: Avoid these places like the plague. Their interest rates are staggering, and you will squander half your income on interest payments. What is it you need so desperate in life that you have to pay 15% interest on it? Answer: Nothing, if you think about it. Learn to live with less.
Used Car Dealers: These places are always in bad neighborhoods and sell questionable used cars for far more than book value, but offer you the "favor" of financing the car for you - "Buy Here, Pay Here", usually by the week. The car will be dead before you finish making payments on it.
Brand New Cars and Leasing: It is tempting, after having had a bad experience with a used car dealer to buy a brand-new car "to avoid all those hassles". But that is akin to saying that you had a bad experience with Crack Cocaine, so you'll try Heroin instead. A new car is very expensive, particularly if your credit rating is shot. In terms of cost per mile, it is the most expensive way to travel. And yet, oddly enough, a lot of brand new cars are sold to very poor individuals, who buy "on time" - or at least try to, before the repo man puts his stinger on the car.
1. Thinking that $3 "isn't a lot of money" so it doesn't matter.2. Not planning ahead for finances, thus being forced to use a foreign ATM.3. Taking out a measly $40, insuring that tomorrow, they will do the same thing. $3 is 7.5% of $40 - but it is only 1.5% of $200.