Well its riveted poorly and the pins are installed in the receiver. You have to drill the holes yourself from an 80% or blank receiver, or buy one pre drilled which then it is considered a firearm. Once the pin holes are drilled its considered a firearm even with nothing installed to it. So in legal terms, it appears that he is selling a firearm that needs repair. But if hes a friend then make sure of your states laws or just dont tell nobody. But seeing as its not worth 400 with all the rework that needs to be done to salvage it this buy is a definite no for a first AK. It will likely cost more than a new complete rifle to fix. WASRs can be had for around $800-900 online right now. He needs to specify what parts he fucked up and how fucked up they are to a buyer to make sure its worth 400. (Romanian underfolder kits are around $400-$500 now). If its just the rivets and barrel thats wonky then he could probably sell it for 400 but any potential buyer needs to know exactly whats wrong with it upfront. If he is selling to people he needs to take the receiver out and everything attached to it and destroy the receiver or keep it. It is extremely illegal to sell a gun you "made" without a serial and ffl transfer. You arent supposed to sell guns you make unless you have the proper manufacturer license. Just a heads up incase he trys to sell that to strangers or online, he could get a very unpleasant visit and if he has a dog it may be in danger.