It's an extra $5 for any game with a base trade in value of $2 (except Saturn for some reason). I've traded in DC, PS1, PS2, Xbox, Xbox 360, PS3, PS4, and Xbox 1 games, and they all got the bonus. Don't bother asking the associate what will and will not work, just let the POS do the magic. That being said, keep an eye on the card reader as they ring in each game and make sure you're getting the right amount. You don't need to be a Pro member, but if you trade in more than $150 worth of stuff, the extra 10% would pay for $15 membership.
I've traded in $250 in the past 2 days, but I do this a lot. If your current or last gen games have scratches, you may get hit with a refurb fee but it's only $.50 for a $2 game and you still get the bonus $5. "Vintage" games with scratches aren't charged refurb so as long as the game looks like it will play, you will get the full amount. You can't trade more than one copy of each game per transaction, so any multiples will have to be split up over multiple transactions and only 4 copies of any one game over a 30 day period.
Check trade in value here:
https://www.gamestop.com/trade/#!...
Other info, scan the last 3-4 pages of the Cheapassgamer thread:
https://www.cheapassgamer.com/top...