I’m curious what your approach is regarding exact accuracy of the dimensions of various buildings and objects. Are you a “measure twice, cut once” type of person or do you just get it started with approximate dimensions and adjust later? I find that I spend a lot of time getting started and planning and that drags things out because there’s not much visible progress. I spend a lot of time looking for reference material and looking at it. Do you just get started quickly and fix things after if they don’t fit?
In my profession I'm an architect so I coming to a project like this with the same way I doing to a real project, from big to small, I start with the general dimensions and shape, measuring it from maps or even plans ,sections and elevations if I can get them, if not I'm using photos to match different photos of the same object from different angle to create the shape, after having the basic shape with more or less accurate proportions and dimensions I moving to the structural elements (beams and columns), after they are in place I can move to the windows and smaller elements on the facade like doors current walls (it's always back and forth, better to fix it at this point before you start drag the misalignment to a deeper stage of the modeling and then it will be harder to fix), and that was my first stage of the terminal, after that I moved to the interior and texture of the exterior.
in this project I'm also added a slop on the flat roof because of it size due to the drainage angle (usual 1.5-2%)
on the interior the same logic, from big to small objects, I started with the floor texturing because it uses as a reference (each element in a building has a standard dimensions, door are 210cm height, corridors has there minimum width and more) in my case from the photos I also spent time gathering and learning the common tiles for the floor are 40X40cm so it can help me measuring distances and dimensions of object when I'm looking at photos, after finishing the walls, floors and ceilings and other architectural elements it's time to move to decorations, furniture and other elements that placed inside the terminal.
in the update you can see that most of the time spent on the signs, I located all of them and make a custom sign for each one of them, the air ducts been placed also according to the real life locations and the lights been hanged up from the ceiling according to the real layout, also I created the cabals that holding them and trim each one of them according to the roof's slope.
It took me time to make some of the custom furniture (there is also a standard there, table are 70-75cm, bars are 90cm and more)
and some other objects to fill the space
there is some other spaces I've been working on but they are not finished or not good enough as a preview in my opinion (attach them here anyway)