Check if in position

Hi,

I've been looking all over the internet and I couldn't find anything.

I'm trying to make an AR board game with real cards in Unity using Vuforia. What I want is before the game starts the player has to put the deck of cards in a certain place. The player knows where to put it because of the border that is displayed on the screen. My question is, is there a way to check if an item is placed in a certain position/place. 

Thank you in advance

Cynthia