When's 0% financing the least costly (best) option?
A Lease is an entirely different way of getting a car. In two situations it makes sense, in all other scenarios it generally doesn't make sense to lease. In the case of always wanting a new car every 2 or 3 years it can make sense to lease. Of course if you drive more the allowed miles you will pay extra at the end of the lease. If you can take the monthly lease as a business expense leasing makes sense. Otherwise you want to pay cash, or get financing. Does zero percent make sense? Sometimes. The only way to make sense of the numbers is to start with your bank, have them approve of the loan first. Then armed with the maximum loan amount they will give you and the rate and the length of the loan, then visit the dealer. You have to run the numbers for your situation. It depends on your income, your other expenses, your credit score, your bank, what deal the dealership is running, how much you have for a down payment. Here is an example. For a recent loan situation I saw: 36 months, 1.49% rate, 20K loan, total interest paid: ~$466. Armed with that information can the person get a better deal at the dealership? There was only one way to find out. In that case the credit union was better. The rebate was larger than the interest paid.
I would go with the family route if I was you. And i think many other people would if they were fortunate to have such a great option.  This will allow you to move faster when your trying to buy a new house because you can easily get a mortage if you see a stellar deal. Also you can establish credit in much cheaper ways than paying the 4% or so on a mortgage. finance a car that you have the money to buy because the interest rates are much lower .9% and you build the credit while paying less interest. Or even better, try and make most of your purchases on a 0 fee credit card and every 6-8 months get a new credit card to have multiple lines of ongoing credit.  to use the mortage to establish credit isnt worth the 4% hit in wealth that it offers. now mind you if your options were to buy the house with your own money outright or get a mortgage i would say get the mortgage because the added leverage would help your investments beat the market most years . figure if you get 6% an average portfolio each year and you can write off the taxes on your mortgage you will be ahead by more than 2% "First of all, I said they aren't as good compared to other options, so I am 100% correct. Second, they are shit and your ""if"" is simply not true.  Even when considering the brand as a whole, they aren't great:  https://www.consumerreports.org/cars-which-car-brands-make-the-best-vehicles-2017/  http://clark.com/cars/most-least-reliable-cars-consumer-reports/" Do you need the car, or is this an optional purchase for you?  Do you currently have a car that is in good working order? If you can continue to save for the car instead of buying now, you'll be getting interest on what you've saved -- and that's a lot better than 0% financing. While I don't disagree with the other answers as far as CD laddering goes (at least in principle), three months CDs are currently getting much lower rates than money market accounts, at least according to http://www.bankrate.com.  A savings account is also more liquid than CDs. Bonds are another option, and they can generally be liquidated quickly on the secondary market.  However, they can go down in value if interest rates rise (actually this is true of CDs as well--there is a secondary market, though  I believe only for brokerage CDs?). Bottom line, A high yield savings account is likely your best best.  As others noted, you should think of your emergency fund as savings, not investment. Excellent question and it is a debate that is often raised.  Mathematically you are probably best off using option #1.  Any money that is above and beyond minimum payments earns a pretty high interest rate, about 6.82% in the form of saved interest payments. The problem is you are likely to get discouraged.  Personal finance is a lot about behavior, and after working at this for a year, and still having 5 loans, albeit a lower balance, might take a bit of fight out of you. Paying off such a large balance, in a reasonable time, will take a lot of fight. With the debt snowball, you pay the minimum to the student loan, save in an outside account, and when it is large enough, you execute option #2.  So a year from now you might only have three loans instead of five.  If you behaved exactly the same your balance would be higher after that year then using the previous method. However often one does not behave the same.  Because the goals are shorter and more attainable it is easier to delay some gratification.  The 8 dollars you are saving in your weekly gas budget, because of low prices, is meaningful when saving for a 4K goal, where it is meaningless when looking at it as a 74K goal.  With the 4K goal you are more apt to put that money in your savings, where the 74K goal you might spend it on a latte. For me, the debt snowball worked really well. With either option make sure that excess payments actually go to a reduction in principle not a prepayment of interest.  Given this you may be left with no option.  For example if method #1 you only prepay interest, you are forced to use option #2. Sometimes I think it helps to think of the scenario in reverse. If you had a completely paid off car, would you take out a title loan (even at 0%) for a few months to put the cash in a low-interest savings account? For me, I think the risk of losing the car due to non-payment outweighs the tens of dollars I might earn. Some things you missed in your analysis:   How will financing change your insurance costs?  I.e. what is the difference between the insurance that you would buy for yourself and what they require?   Note that it is possible that your insurance preferences are more stringent than the financing company's.  If so, this isn't a big deal.  But what's important is to consider if that's true.  Because if you'd prefer to drive with only the legal minimum insurance and they insist that you have full coverage with no more than a $1000 deductible, that's a significant difference.   Remember that you don't have $22.5k for six years.  You have an average of $10.5k (($22.5k + -$1500)/2) for six years.  Because you make payments ($24k) throughout.  So you start with $22.5k and subtract $333.33 a month until you reach -$1500.  That neglects both investment gains and potential losses.   It's not the $333 payment that will freak out mortgage companies.  It's the $24k debt.  But that's offset by your $22.5k in assets at the beginning.  And the car of course counts as an asset, albeit at lower than its sale value.  I.e. from the bank's perspective, paying $22.5k for a car out of savings is almost as bad as borrowing $24k for a car.  Both reduce your net worth.   Watch out for hidden fees.  In particular, 0% interest can often change into higher interest under certain circumstances.   If we assume a 7% return for the six years, that's about $1400 the first year and less each year after.  Perhaps $4500 over six years.  But you aren't going to get a 7% return if you keep $24,000 in a bank account in case you have to pay off the loan.  Instead, you'll get more like 1%, less than inflation.  Even five year Certificates of Deposit are only about 2%, right around inflation (1.9% for previous twelve months).   You can't keep the $24,000 in a securities account and be sure that it will be there when you need it.  If the market crashes tomorrow, your $24,000 might be worth $12,000 instead.  You'd have to throw in extra money from elsewhere.  Instead of making $4500 at the cost of $1500, you'd have paid $25,500 for $12,000.  Not a good deal.  So for your plan to work, that $24,000 needs to be in an account that won't fall in value.   You either need to compromise on the idea of a separate account that is always there when you need it, or you have to accept rather low returns.   Personally, I would prefer not to have the debt and not to pay extra on the insurance.  But that's me.  The potential investment returns are not worth it to me.  If you give up the separate account, you can make a few thousand dollars more.  But your risk is higher. "Using the fact that you'd save $160/mo by spending $7000, I'd look at it this way -  If I were to lend you the $7000 at 12%/yr, $160 would pay it off in 58 months. At 18%/yr, 72 months or just 6 years. You can run spreadsheets to get breakeven scenarios, and mhoran is on track with his answer, but breakeven is just one point to consider. Beyond that date, it's free money.  My approach is to look at it with a question - ""How much interest could I afford to pay to make that monthly savings worthwhile?"""