You’ll need things produced by many of these professions to optimize your character, but you only get two professions you can do yourself. Unless you want to grind on a second character to collect all the reputation-gated recipes for other professions, you will probably need to buy the stuff you can’t make for yourself on the auction house. And if the price of the stuff you need exceeds whatever your questing and your followers are bringing in, you might want to sell some of your own trade goods or raw materials in order to finance your purchases.
Most BfA Alchemy recipes have 3 ranks. Rank 2 reduce the materials required to create a recipe, and Rank 3 have a chance to create multiple potions/flask etc. Higher rank recipes also give skill points much longer, so it will be a lot cheaper to level Alchemy if you first get Revered with the new BfA factions, because you can use cheaper recipes for longer.
Another dungeon farm, this time in Uldum, Tol'Vir trash mobs drop loads of embersilk cloth. Stacks of this tend to sell for a tidy profit, though prices vary depending on the realm. A typical clear of the dungeon takes about 5 minutes, netting about 7.5k per hour in cloth, vendor trash, and various other drops like mats and BoEs. Pick up a Potion of Treasure Finding and farm to your heart's content! It's just as profitable on normal mode as heroic, too, making farming all the quicker and easier.
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