Its fairly idiotic to not finance a new car assuming you can get a low interest loan from the credit union. Inflation runs 2%. A credit worthy borrower ought to be able to borrow below 4% from his credit union anyway. Make a decent down payment on a reasonably priced car. A used car on the other hand, should be paid for with cash if at all possible.
So You pay maybe $5,000 down on say a Mazda 3, pay about $275 a month on the loan. At the end of three years, you have 45,000 miles on your car, all repairs covered by warranty. You have $13,000 out of pocket. It will be paid off in two more years, at 75,000 miles, certainly last for another two years after that. The car of course has been maintained to your standard. Your trade-in has an inflated value in this environment, so it should be easy to make a little more of a down payment and get the monthly nut to 200 bucks. Easy.
If you bought a used car for $11,000 cash, it starts out with 40,000 miles and has little or no warranty. At the end of three years, its now six years old and has 100K on it. I don't subscribe to the point of view that a used car is necessarily "someone else's problems" but there is always that risk.
I'm a big believer in buying used--most of the time--I'm just saying you have to adapt to circumstances. Five years ago the percentage play was to buy a five year old off lease luxury car for peanuts. In 1989 you would have to pay well over 10 percent interest to buy a new car. So you paid cash if you could. The percentage move right now is to finance a car that is well within your means.
P.S. Did you know the college aid people don't take into account consumer debt in fixing your kid's tuition? If you have a kid who will be enrolling in college during the term of the loan and you have the option of paying cash or financing, you pay cash. (Colleges take into account cash on hand, of course in setting tuition). But not too fancy a car,or they will penalize you for that.