Interacting with models in AR

I do architectural visualization, and I've been experimenting with Vuforia.

I'm building an app, in which I feature 3 models. I decided to not make a traditional menu with GUI buttons to let the user choose between models, but a more interactive way: when the app launches, the miniatures of the three models are placed side-by-side on the marker, and when a user would touch the appropriate model, it would have a scale animation to take up all the space on the marker.

So what I'm trying to achieve (I have some programming background as well):

Add an event listener to the three models, and when one of them is tapped just fire a method that will do all the animation logic of the appropriate models.

My problem is that for the world I can not understand how to add an event listener, or even how can I get feedback from a tap on a model.

Could someone please run me through how should I be doing this?