Im trading for a quad and need some help

Hello im new to Polaris atvs and someone has offered to trade me a 2006 Polaris Outlaw 500 for my 87 Honda Trx250x. The problem is the Outlaw starts and idles fine but doesn’t respond to full throttle. The person does not know whats wrong with it. My concern is trading my quad thats very clean and has no issues for the Outlaw.

So i would like to find out if anyone knows what the problem might be with the outlaw? Also is it worth trading my 250x for it?