You must provide evidence that shows that you either understand more about Bitcoin than the average newbie, or that what you want to post can only be done in another forum.
I made a purchase in the goods forum and want to vouch for the seller in his thread. I don't mind if you set me back to noobie mode after I've vouched for the seller.
Who did you buy it from? If that person is trustworthy and would vouch for you, I could whitelist you.