Game pass GUI?

So i'm wanting to make a game pass that triggers a script so that when it is bought a gui will come up saying things like teleport to stage 15 or something like that. (i'm making an obby by the way) i'm also using this model http://www.roblox.com/Obby-Infinite-Checkpoint-System-NEW-item?id=175773771

Can someone please help me?