I'm thinking one more bigbuy before I go off to college in January and become a poor college kid. So what should I buy? The limit is ohhh $300. Suggestions, comments, concerns, love to hear 'em.
HMMM well i guess seing as you posted this in performance thats what you want... sorry im slow.
You already have CAI and cat back, so you could get a header and a cat to finish it off.
TurboTec Racing is going to be having a GP on pacesetter headers and magnaflow cats.
I tihnk the price is $219 for a ceramic coated 4-1 header and $62 for a 2.25 cat.

That would be really cool. I was looking at those used, but the people I was gonna buy from disappeared. Awesome suggestion! Any others?
How does one go about buying something using a group purchase?
That depends on the GP.
I was given a discount code to buy off a web site. I used my credit card.
Some buyers use paypal, check, MO, credit cards. It all depends. Just ask the seller in the GP. Most sellers will find a way that fits you.
I plan on getting the Magnaflow cat from turbotec when that GP starts soon. I dealt with TurboTec once before, I was 100% happy with everything.

Very enlightening, thanks.