18'' solo x

im getting a 18'' solo x with two 2000watt amps and i was wondering if i needed a whole battery for the amps or can i just use the car battery and buy an alternater? How much are batteries and alternaters?

I'd start off with a H/O alternator, and def. upgrade the big 3....depending on the car, a good price as far as an alternator would be (guestimating here), $300 or so.

what amps are those?
a yellow top runs $220ish.