I agree -- it comes down to how you view money, clothes, and your social obligations.

At my college it was unheard of for a student not to lose or gain weight. Most fluctuated between 5-30 lbs. 5 lbs either way may fit, but by the end of my first semester I had dropped 2 dress sizes. My jeans from before college just didn't fit. If I had 500$ at the start of college -- I would not invest in anything. I understand it is different for everyone and every school.

In consideration of trendy it really depends on your social situation. In many situations classics will work. However, I majored in three different things in college that had three very different atmospheres and social obligations of dressing. Wearing unstylish clothing in one would not work. Not just with the students, but the professors as well. In a major largely about networking - this was a big deal. The styles didn't necessarily need too be trendy, but most certainly your clothing was extremely important to conveying personal style and "classic" styles were looked down upon. Wearing the same jeans everyday? Yeah, no. It was commitment or scorn. In one of my majors, style and trendiness were looked down upon. You could wear your boy cut or boot cut jeans and no one would care -- unless you dressed super stylish, well, or off the wall (goth, grunge, or prep for instance). They hardly took showers, rarely looked up from their textbooks, or were on so many drugs they didn't care unless you stood out. Professors didn't really like working with girls they thought weren't serious (i.e. cared more about makeup or clothing than studying). While this isn't right, when you learning the subject is contigent on their help, it seriously sucks. If you can do it without their help -- props. In my final major it didn't matter grade-wise if you were dressed well (unlike the first), but it was incredibly focused on trendy clothing. They were very opinionated and would publically humilate those who were too busy to do makeup, engage in social customs (I.e. eat something other than vegan food), or didn't dress like a basic b*tch. Many social situations like bars or having wine with professors or going to an international science conferences have very different social obligations and clothing obligations. You don't have to conform -- you never do, but networking at these events (which is a large part of college for most majors) is much easier when you chose to conform somewhat.

It also matters what your upfront money is. When you have 500$, what do you spend it on? Will you get more later? People with more money and know that they will have more in the future (in case they get asked to a winter formal, a themed frat party, a Halloween party, or a backpacking field trip) would just be able to invest in nicer stuff upfront and buy nicer stuff when those situations arise. However, that wasn't my personal experience in college. I couldn't afford to drop 100$ for every random invitation that came up. Having the most versatile -- if perhaps not the sturdiest -- wardrobe was more beneficial. Also when the clothing inevitablely got ruined (Damn you intaglio) I didn't cry as hard.