OK, this is a guide about what not to do.
A few months ago, when I first started to learn about systems, I had an old friend come up to me and try to sell me two twelve inch Kicker Comp subwoolfers in box for $70.00. The box was rough and one of the terminals had a loose connection on it. However one of the subs had a hole punched through it, but other than that, they work and pounded.
So I thought, okay, I'll just put them into another box. I wanted to mount the subs on either side of the trunk so I wouldn't lose all my trunk space. I saw two twelve inch subs boxes at Wal-Mart that fit just about where I wanted them but, they just didn't look right. So right there, I wasted $77.00.
So as of now, I've wasted $147.00. Still do not have an amp, not wired for an amp, and everything looks like crap in the trunk.
So the moral of this story, wait. Buy new stuff, build a box that fits and isn't roughed up at all. Don't buy the first thing that comes along.
As of now, I'm gonna keep the subs in my trunk for show (

), sell all my old stuff, try to break even, and then start from scratch. All this after my mom gets off my ass about my system and wasting money.