Trigger collision on complete overlap only


I’m trying to make a trigger collision volume and have it trigger only when an object completely overlaps it.
The default behavior is that the “start overlap” trigger when an object touches the trigger.
I’m trying to get it to trigger only when an object is completely inside the trigger volume.

In practical terms it would look similar to a city building game where you can place a building but only in a specific zone and the building has to be completely inside that zone.
I was thinking about having 2 trigger volumes, one that the ‘inside’ zone and the other is a ‘border’ outside. With ‘inside’ trigger opening a gate and triggering an event if the object is not touching the ‘border’. But I’m hoping there is a better solution. The other option I read (but have not tried) is inverting the normals on the collision mesh, if that is possible is it possible to invert the normals through script?

Hope someone can help, and thank you in advance!