Buying used beauty products
You'd be surprised what type of bacteria lingers on used beauty products, so when you're trying to save money by purchasing used and/or open products, you're also getting someone else's germs or diseases. Even purchasing open perfume can be risky. You never know what's in there, especially if you're not familiar with the person selling it to you. This is especially important to avoid if you have sensitive skin.
Stalling on going to the doctor
All this usually does is make the problem worse and you're going to need more medical care than you would have if you had gotten things taken care of in the first place. Rather than skipping on the care, work with your doctor and the billing department to come up with a payment plan.
Buying used safety products
It can be incredibly dangerous to buy used safety products including children's car seats, bike and motorcycle helmets, fire alarms, fire extinguishers and carbon monoxide detectors. You don't know how many times the products have been involved in accidents or have been used and the damage, use and wear and tear isn't necessarily visible. Avoid taking risks by buying brand new safety products instead.
Doing DIY projects you can't handle
It's not an uncommon scenario. Some think they can handle a huge project of which they have zero experience rather than shell out the funds to have someone else do it. Later on they usually need to call a professional anyway to fix the initial problem plus the damage that was caused by the attempted repair. If you've never done a specific DIY project before, you're better off hiring someone to do it or at least have friends assist you who know what they're doing and can teach you the ropes.
Buying used electronics
There are many types of electronics including laptops, TVs and DVD players that you should buy new instead of getting second hand. They're so sensitive that getting dropped or knocked around could cause quite a bit of damage. You don't know how many times they were "injured" before you got your hands on them, so even though it's expensive to buy new, you're better off doing so. Otherwise, you could shell out money for a used item you're just going to have to replace not long after anyway.
Buying junk food
Junk food, unfortunately, is usually cheaper than buying healthy food. However, more stores and restaurants are realizing that people want healthy food choices and they're making it happen. Even on dollar menus at fast food places you'll find yogurt and salad. Eating junk food may seem like a cost efficient idea, but it won't be in the long run when you start experiencing weight gain and health problems. Opt for low cost healthy options instead and you'll reap the benefits.
Cutting your own hair
There's a reason stylists go to school to learn how to cut hair. Let them do it for you before you end up looking absolutely ridiculous.