How to replace assets with scripts

Hello everyone, I am trying to create a “time travel” project showing the urban development and changes in the last few decades. I have created 4 different models (same geographic location) on Blender and imported those models into Unity. They show up as 4 separate “assets” in Unity (not terrain). I am planning to create an User Interfaces panel with 4 buttons, which allows users to navigate or select the “year” they want to travel to. The user will also be able to “walk around” (first-person AI).

I am wondering what kind of scripts do I need to “switch between” the models I created. Thanks.

I would use the scene hierarchy to accomplish this. I would create an empty GameObject for each year that can be visited, and put all the building for that year, under/inside/children of this empty object.

Now your script to change “viewed year” need only activate a single root object, and deactivate the previous one.