Being the nice older brother, I decided to co-sign for my baby sister on her first car. She had a job, was very responsible (so i thought), really didn't drive much, and lived with my parents. That was part of the problem. My mother is horrible with money...and she paid my sisters car insurance. This is just going to go downhill from here. My sister decided, "Hey why do I have to pay for a car" and every month on the 21st I would receive a call from CarMax Auto Finance...for two years. I would call my sister every month with a WTF moment. I finally realized that this was no longer our debt, rather it was my debt. Well needless to say, I paid off the car; she made about four total payments. To top it off, she wrecked the car - good/bad in that I would get the insurance money....oh wait, I guess in order to have car insurance, you must make your monthly car insurance payments. Ugh! Lesson learned: when you co-sign, it is your debt :)

Paying off those monthly car bills must have made a real dent in your wallet! But imagine if you'd gotten to a point where you couldn't afford the payments! What would have happened then?

Really great lesson - co-signing means that you own the debt.

I certainly hope your sister has apologized!

My worst money mistake was taking out student loans in college and just using what I needed. If there was any money left from the loan after paying for tuition, fees, and housing, the school would give me a check. I had the option of giving that money back, but instead I took the money and spent it. Now I owe more money in student loans than I could have ended up owing and because of that I have to keep deferring my loan payments because I can't afford to make the monthly payments. Even if I had saved or invested the money I got back would have been way better than just spending it and having nothing to show for it. Now it's going to take me even longer to pay the loans back!!

Buy & Hold: I asked my financial advisor and my CPA if I should exercise my Lucent options. My Financial Advisor said "OUR experts say ACCUMULATE". OK. My CPA said, "You already pay so much income tax, you won't be hit by AMT."

I excercised my options and bought the Lucent stock on a margin account. Then held the stock as it fell from $70+ to $3 per share. Oh, and I had to come up with $35K to pay the AMT.

I fired my Financial Advisor and CPA and learned the hard way to tdo my own research and trust my own judgement.

Biggest mistake was a missed oppurtunity, like Lynn's. I grew up in rural Oregon, where our power was provided by an electric co-op, and so once a year, there was this big co-op meeting (since we were all "stakeholders" in the co-op). Cookie and pie contest, free hot dogs, that sort of thing.

But they also had an auction, where they sold off some of the co-op used equipment. Including, in this case, a Jeep Wrangler that was a repair vehicle. Went for $1,500...and I still kick myself for not bidding. It was a fantastic deal (I know they took great care of their fleet) and even though I got a nice, cheap car later on, I still wish I had jumped on that.

The following is much less embarrassing when it's in my head. Typing it out, I cannot believe I ever let this happen.

I thought it would be a good idea to apply for a new credit card in order to transfer my one existing card's balance for a lower rate.

I applied and was accepted, balance transferred, but the balance was just about at the new card's credit limit, so close to the limit, even, that the new finance charges could push me over the limit. Didn't see that coming!

Shortly thereafter, my finance's car broke down, and since he relied on his car for work and didn't have money to fix it, I put the repair on my old card, nearly maxing it out.

My finance, of course, never reimbursed me for the cost of the car repairs (oh, the shock), and rather than deal with the bill, I ignored it, convinced in my righteousness that the debt was his responsibility, not mine. Genius points awarded to: moi. By the time I copped to my mistake, the card was in collection.

In the meantime, I fell behind in payments to my other card, exceeded the limit and hit with major fees.

That series of small, very misguided decisions affects me to this day in being behind in savings and my credit rating. What I learned?

A. I will not put myself in a position to offer financial help to anyone else unless I am in good financial shape
B. When in a committed relationship, never make up how joint finances will work on the spot - have a plan.
C. I never lull myself into thinking credit card companies make decisions in my best interest
D. Live within my means to make credit only a pure emergency backup.
E. Save, save, save.

Oh, goodness... my husband and I have made a few. The worst, though, would have to be not keeping track of our account balances. It's easy to make wrong estimations when you have multiple credit, checking, & saving accounts and don't make a point of checking them together and totaling them up. When we finely did do that, we were shocked out how bad off we were. I mean, we knew it wasn't good, but we didn't think it was half as bad as it was.

Since then, we've started tracking our accounts TOGETHER on a spreadsheet weekly, and then recently biweekly (after each paycheck). Since we started doing this we've turned things around and are making better and better progress.

I think my worst money mistake was not becoming a "saver" earlier on in life. My parents never taught me the value of saving money, and although I worked hard and put myself through school (I was about to do it without a loan by working full time), I spent every extra penny I had on "stuff". Thankfully I never got into the credit card debt trap, but it was touch and go there for a while!

It's only been within the past 2-3 years (I'm now 30) that I've really begun to understand the value of having an emergency fund, and savings on top of that.

I cringe when I think of all the money I blew when I was in my early 20's!

My worst financial mistake was buying a sports car that was a dealership demo. Although buying it as a demo saved me some money off the new car ticket price (which I never would have paid), how would you drive a sports car if you were a salesman and used it as a demo? Yup - you'd have fun with it too.
So wasn't mud on my face when I turned around to sell it and discovered that it had been in an accident - I took a very big hit on the sale of that car.

Speaking of cars, I was sold one in Australia based on it's spectacularly low mileage, only to discover two days after driving it away that the odometer only sporadically worked.
I guess buying cars in general is not a financial forte of mine!

My worst mistake is one I share with my dad: at the beginning of my senior year in college, two days before my 21st birthday, I crashed my car. No one was hurt, and the damage was only extensive in the front end, but the car was so old by then that it was totalled by GEICO, and I wouldn't be getting any money from them because I had minimal collision coverage. I had a part-time job, but no way to buy a new car. In an astouding act of generosity, my dad gave me $1000 for my birthday, which I could use for a down payment. Then (!) a few days later, I got into yet another car accident, as a passenger this time, and was badly injured and hospitalized for two weeks. Buying a car became a distant concern, and my dad agreed to hold on to that money and invest it for me in a good stock. He bought $1000 worth of Apple shares, which would be mine whenever I was ready for them. iPods were new on the scene, the stock rose and then fell some, as stocks do, my dad needed rent money and within the year had cashed out and spent it. I think at the time he was reading "Rich Dad, Poor Dad".
Now, of course, it's all water under the bridge, but I moved to a city where I don't need a car, and I handle my own investments these days.

My worst money mistake?

Verizon billed me some ludicrous ammount and sent me to collections in college. After finding out about it, I called them and it was a mistake on their part. They wiped the bill clean, apologized, and said they would clear it up with the collection agenices. I never followed up until after college. At which point I realized the incident was still affecting my credit and I had no reference numbers or anything from the college incident.

Now, when I speak to any company's rep, I ask for their representative number or id(do this before the conversation begins), and always request a confirmation number of some sort. Always do this.

When I first moved to New York City, the first landlord i rented from insisted that we pay 3 months of security since my roommate and I didn't have much established credit. Even though we had good jobs relative to the rent, and also co-signers, they insisted and we paid. It turns out doing just a little homework would have been a good idea-- its illegal in NYC to take more than a 2 mos security deposit. Unfortunately, most of that money we never saw again..

this is more of a missed opportunity than a blunder. in 2003, i decided to invest in the stock market, investing only $1,000 which i figured was the most i could afford to 'lose.' it was the dawn of the ipod revolution, and i figured buying apple stock was a good idea. the price was $17/share.

in 2005, i cashed out when the stock reached $75/share. today, apple stock is worth $140/share. %$#$@!!!!!!!!!!! i certainly didn't lose, but my impatience caused me to flip something i should have held for years to come. lesson learned: the stock market isn't vegas. short-term gains aren't good goals for the amateur investor.

putting a semesters worth of gas on my credit card

It has taken, since college, over 5 years and two layoffs within a 7 month period for me to realize the importance of an emergency savings fund. But I'm happy to say that it's on the way now! Not having that fund available was the biggest mistake I've made.

I don't give any to Thrive.

My senior year in college, I was short $5 grand for tuition, so instead of increasing my loan, I charged the tuition onto three separate credit cards!

The interest rate shot up to around 20% on all of the cards within a year. I still don't know when I'll get these things paid off... How's that for a huge mistake?