I think he mentioned that the trigger was loose/rough.
But that was a pre-ban Chinese AK. In good condition a $1500 rifle all day long. Picking it up for $100 leaves you a LOT of room to fix it. I would have just taken it to John at M-13 Industries (he's an AK expert), and I bet he would have had it up and running for just a small investment. Probably under $100-200.
Trigger axis pin hole was large. Chances are it may need a new reciever from axis pin “egging” from not being properly heat treated. On the bright side, someone may just have to fabricate a new slave pin for the axis pin to go in, then just heat treat the axis holes....and then voila...spiker for $100. Deal of a lifetime.