he's saying that prebuilt rails are going to set you back over 200 bucks man. They are NOT cheap.
Also... the "hitting that white box" comment was to direct you to the searchbar, where you can find this info without posting a new topic.
My suggestion would be to build one yourself.... If you want to buy one, go for it.... it's gonna be really pricey. I can't remember names off the top of my head, but you can find some by searching.