What would be a good amp/sub/box to get?

theres this place called "hyperpulse" near me, where i know this kid who sells car audio stuff that "falls off trucks", but we're not really that tight so he prolly won't do it for me. But yeah i'm not going to spend like 2309523 dollars on a ****ing car audio system, bestbuy is good enough for me where i can get like half off... although i ****ing HATE trunk rattling... i dunno i might just say **** it and not do anything, and just use my car stricly for transport and spend my money elsewhere, like starting up a porn dvd archive.. its all too damn complicated