This is a question ive always wondered, whats the first step? do you guys block out the major/bigger parts first? or do you guys start small? does these type of buildings really require external help from 3d modelling software like blender or it can completely be made studio just fine?
I think maybe it is possible to do it in Studio itself, but at the end of the day, it’d be better to learn blender and use blender instead. You could also use blender for things outside of Roblox.
But I am not a builder by any means, but I do use Blender quite a bit for my projects, and it always works well.
It’s possible to do it only using roblox studio, with some parts, unions etc, but honestly it will requires a good pc to avoid lagging, so talking about performance you should consider using blender/others 3d progams, maybe substance painter 3d to good textures, and you gonna reach to this result and have a good optimization too
If you want to know the order of building a scene like this, for me at least i would say i get start from the big parts, i start placing the walls and placing some regular parts to have a preview of what want, after that i start detailing the small parts
Example of the same scene that you shared:
You always start big. The general rule is 80-20: 80% of the scene should contain 20% of the detail, and 20% of the scene should contain 80% of the detail. The scene you showed doesn’t adhere to this principle, and as a result, it looks cluttered.