I built my own "architectural model" using foam core and balsa wood. I did it carefully to scale, had plans of my own terminal to go, sort of based on existing facilities but essentially generic. You can find materials at a hobby or art store. Architectural model materials can be had a specialty store, or online vendors. Son of an architect, I had it in my blood to try it.
Here are some professional examples. 1:500 and 1:600 scale seem to be common, so I bet that actual architect model supplies (such as trees and cars) can be found to match. I never tried to add those elements.
This one is 1":40", or 1:480, very close to the 1:500 of Herpa models, which I think they use.
This one is 1"=50', so 1:600 scale, TUL
Airport. To me it looks like they are using Schabak models, particularly
This one of Cologne Airport (CGN
), 1:500, looks like it's entirely foam core, not much other detail. Easy to do. It works for CGN
, layered geometric shapes.