There are some differences between the factions you are going to want to WOW Classic TBC Gold know about, too. Orcs and Humans are functionally the same, with workers manually chopping down trees and evaporating into gold mines to collect gold, then walking the resources back to your Hall building. Therefore, you'll need Halls as near gold mines as possible. If, for any reason, you need to build one additional than the minimum space, you will need more than the five employees to compensate for the lost time.
Night Elf workers, called Wisps, want to Entangle a Gold Mine to collect from it, which takes 60 minutes. Once built, Wisps can be'loaded' to the mine, amassing gold without needing to move. Being the ecological sort, they also don't destroy trees while gathering lumber, like the other factions. Pop a wisp on a tree, and it'll float around collecting lumber for the rest of the match.
Like Night Elf Wisps, Undead Acolytes remain about the mine and collect automatically. In 100 seconds, construction one is slower than the Entangled Gold Mine, but Undead Acolytes do not need to stay around in one place to construct, rather summoning a portal that attracts their constructions into existence. Once the portal is summoned, they are free to start other tasks.
Undead also differ in the other factions in that they need to utilize their simplest combat unit -- Ghouls -- to gather lumber. They are also much more defensible, should your opponent target your workers.
Night Elf or Undead players will find their beginning mine ready to use, won't have to be worried about Haunting or even Entangling immediately, until,the very first Gold Mine collapses. That's correct, Gold Mines don't last forever, so you'll be looking to expand quickly into the cheap TBC Classic Gold ancient mid-game. Locate a second gold mine early, and start planning to clear the region and expand to a second base. You also want to watch for your competitor's expansions. If you have two gold mines, and they've only got one, you are going to be at a serious advantage.