Trying to help save money

I know the question of the correct sub has been asked 1000 times. But I am kinda in a hurry and dont really have time to look through all of the forums. My cousin is currently looking for a sub or 2 for his cavalier. He wants to spend 300-400 total (box, sub, amp, wiring, etc.). Well he wants to have 2 of something just to say "hey i have 2 10s in my car what do u have or 2 12s" or whatever. I told him for the money get a decent 12 and have it sound better but he doesnt really want to do that. I am still thinking he should be looking at a 12 sub with a decent amp. But soon he is looking to buy an Explorer or some kind of SUV


1. Anything I can tell him so that he will take my side about getting the sub number to 1 and having it be better? 2. What sub/amp combo would be good for this application? 3. Should he wait and buy when he gets the other car?


Any Information would be greatly appreciated.

Whats he looking for SPL (loud) SQL (kick ass sound) or a little of both.

Tell him to look into a single 15. Or if he wants 2-12's then he can look around. Heres some sites to get you started.
www.incriminatoraudio.com
www.reaudio.com
www.soundsplinter.com
www.adireaudio.com
This should give you a start tell him to stay away from audiobahn, sony, legacy, pyle nad any other cheap brands that you can either get from a flea market, or walmart.