How much should I sell my gamecube for?

Hello. I currently have 240 dollars and I am trying to save up for a PS3. I called gamestop and asked them how much it would be and they said in the 340 range which included tax. I want to sell my gamecube to come with some more money but I don't know how much to sell it for. I was thinking between 75 and 100 dollars but am not sure. It is silver and is in great condition. I didn't use it that much so it runs just like new. I have 1 controller, 1 memory stick and 4 games. The games are, Metroid Prime with a bonus disc, Sonic Mega Collection, NFL Street 2, and UFC throwdown. Please feel free to reply with your suggestions. Thanks.

GameCubes in my area's GameStops are selling for about 30 dollars, so I suggest you sell the games separately somewhere else and sell the GameCube to GameStop.

Last time I went to a Gamestop they were selling GC for $30 so....

Thanks for your input.