How much money does GameStop buy used games for?

For instance, today I'm going to sell these Nintendo DS games at GameStop for in-store credit (I want to buy a game while I am there)



Super Princess Peach

Rubik's World

Kirby Super-Star Ultra

Animal Crossing Wild World

The Legendary Starfy



All are used but in like-new condition, and they all still have their cases and instruction booklets. How much money do you think I'll get for them?How much money does GameStop buy used games for?
Depends on the popularity. I wouldn't sell them at gamestop in my opinion I sold my one game there for $5 and they sold it for $15 so I think it's better to sell on craigslist or something along those lines.How much money does GameStop buy used games for?
Just call them and then you'll know.