A car? For Boulder? Haha. I believe the correct answer is "a bike". There is really hardly any need for a car in Boulder, especially if you are a student. You can get a good bike and solid U-lock for $500 or less, keep it maintained for under $50 a year, register it on campus for only $10, have free parking everywhere, and be proud of yourself for keeping the environment and your body in great shape (just think about how beefy your thighs will be after biking up the hill to campus every day for a semester!). Also, your student bus pass gets you access to all buses and light rail (which are really quite convenient), and the bus system in the Boulder/Denver area is really good. And for when you really do need a car, an EGo CarShare membership is only $25, and their rates are reasonable considering how much money you're saving by not having a car. Although I guess your parents are probably paying for it if you're looking at a BMW or a Lexus...

Still, my opinion is in line with the good old Boulder cliche - ditch the car and use your own two feet, a bike, or the buses to get around. It's easier than you'd think, cheaper, and much less hassle than owning a car (insurance, gas, parking, maintenance, registration, etc add up big time).

For traveling within Boulder, get a bike or a skateboard.
Only if you have to go around (Like to Denver and choose not to use the RTD, would I recommend a car...)

PS: BMW 330xi

I like the BMW 330xi but honestly you don't really need a car to get around boulder