re: If you want to own an AR-15, you should build it

what are the special tools? The video i watched the guy did have a special wrench but he said he couldn't use his standard AR wrench because of the brand barrel he bought. Other than that he had the rubber vice block.

fwiw, my "parts list" for the upper includes: barrel, stripped upper receiver, BCG, upper parts kit (includes gas tube and build out parts for the stripped upper receiver), gas block, hand guard, and flash suppressor. Those items appear to be what would come with a complete upper.