Engineering is a crafting profession that primarily revolves around fun recipes. The gold-making potential from engineering is limited in terms of Legion recipes. The Skullblasters can be obliterated for profit. Engineering has a lot of profitable old world recipes, primarily mounts and various unique effect items and toys. This profession is best relegated to an alt unless you love the lore-aspect or have other sentimental reasons to keep it on your main.
Now that we have a lot to post we reached a point where we have to plan what items we post on an 12-24-48 hour cycle. The auction house fees for Warlords of Draenor items are extremely high. And the values of the items are really screwed up. A lot of the weapons or armor has an item value of 5-10.000 Gold. But they look plain bad and the chances of selling them is pretty low.
Charge Into the Warfronts: Fight on the battlefields of a large-scale, 20-player cooperative Warfront to claim a key strategic location. Capture resources to build your faction’s forces, lead the charge as your troops lay siege to objectives, and fight the enemy commander to claim victory in this new PvE mode inspired by classic Warcraft RTS battles.
To use it as a bank, figure out how much you want to have on-hand on your character based on how much you normally spend on repairs, food, ammo, etc. and send the rest to the bank alt. The principle here is "Out of sight, out of mind.". Money "you don't have" cannot be spent, requiring you to log out of your character, and then to log into the alt.
If i start on a new realms, I am farming a lot of transmog from classic and Burning Crusade Dungeons and Raids. In the beginning, i start to post them if they have at least a DBRegionMarketAvg (Average value of an item on all EU realms of the last 14 days) of 500 Gold. All the other items get vendored. The time you hit a stock of 1000 Items, my value treshold raises to around 2.500 Gold. All the items below that value get vendored aswell. Newly farmed items that are above these treshold will be listed. Why? If I start over somewhere, I want to get a certain amount of gold quickly. Cheap items are great for that. Later on, to save time, Quality is better than quantity. As mentioned above, re-posting the items on the auction house takes quite a bit of time. At this point, I can recommend you the TradeSkillMaster AddOn, it makes your auction house work really a hell of a lot easier.