Don't spend All your money on Evergreen!
Say you need to build Bulwark supports in 1/87 or 1/72 or yes even 1/160. Or 1/48! There's another source. Train Shows or shops that specialize in them. The scenics surrounding Refineries, Mines and Fuel Depots are incredible for the chotskes you might need. Bridges(The Steel Truss type have lots of parts in all scales too!).
So go to a train show and look for those little stapled bags of parts in the scales that will work for you. Sometimes all you have to do is cut them off the sprue and promptly use on your project. This applies to Armor too. There many parts to make Turret Baskets and Gear Racks. Also, You have a lot of tools in those scales as well.