Many players who already have higher level characters create alts that they level to a certain point and then stop. Often, these twinks are level 18-19, 28-29, 38-39, etc. for the purpose of going to battlegrounds at the top of their tiers and kicking butt. Since these twinked characters are owned by higher level players with lots of cash, they usually outfit them with the best gear available at their level. Thus, items that require level 17-19, level 27-29, or any other items around this level, with good stats or dps, often sell for much higher prices than they normally would. This is especially true on an older server, and also especially true of blue (rare) items. In general, "good stats" include Cloth "of the Eagle" (for mages, warlocks), Leather "of the Monkey" (for hunters and rogues), and Mail "of the Bear" (for warriors/paladins)as well as weapons with these suffixes that can be used by the right class.
Another potion of treasure finding farm that was made extremely popular by the YouTuber Oldbess. In this spot, you are simply to patrol the entire southen river basin in Twilight Highlands, just around the Verrall Delta area. The goal of this farm is to kill water elementals for their volatile water, which trends around 50g per drop. Combine this with the cloth and the treasure chests, and you have a cool nifty farming spot – thats rarely populated these days.
I generally hate this farming spot, although I remember alot of farmers coming up big here. For my liking the drop chance on the sprite darter hatchling is very low and I couldnt ever come up with one during this expansion. HOWEVER, if you do get one, you an make out BIG - as this pet is non-existent on pretty much every server's AH. Did I mention it goes for a stunning 150,000g? Yup. Then add to the fact that many players LOVE this pet, especially girls for some reason... And you can make a big profit if you get one to drop. Honestly I hate it, it just rubbed me the wrong way. You can find it in new thalanar, on the very east side of feralas. Good luck.
Similar items to peacebloom that are profitable on most servers for people getting started include: Hypnotic dust, Celestial Essences, Relics of Ulduar (and other rep items), and heavenly shards. The same can be said with the earlier wrath enchanting mats, they are still valuable for casual players or those without a lot of disposable income! This list is not the end all be all of making quick money! Check your scan results daily and add to this list and you will be on your way to hitting the gold cap much faster than those who quest or farm!
You earn a large rested experience bonus when you log out in this rest areas. This gives you a massive 200-percent bonus to experience gain from most actions (though experience from quests isn’t included). The amount of rested experience you earn increases the longer you’re logged off, and your experience bar will be blue (instead of purple) while you have the bonus.
There's a good chance you can buy the raw materials for 25% - 75% of the going rate of the finished item, or mine them for free. The fee for an 8 hour auction is only 1 silver, so you can afford to re-auction rods that don't sell the first time. Be careful of making too many rods or other parts of a kind at once, though, as you may get stuck with them for a long time when others produce the same item and set a cheaper price to it.
Isle of Quel'Danas: Special mention. At lvl 70 you can start doing the dailies here. Despite not being able to fly, the quest density is VERY high. I recommend hitting this every reset if you spend more than 24 hours REAL time(not /played)in the 70-80 level range. In fact, if you're doing a monk and only logging in once each day anyway, IQD WILL be your best exp/h for this level range.
Quality gear. These can be greens, rares, whatever. However, always think, "Who needs this?" Items that have stats like Stamina are typically useful to all players. Items with stats like Spirit are only useful to a subset. Items that combine two highly sought-after stats, like Stamina and Intelligence (which all casters need) will sell for more than items that combine two stats like Agility and Spirit (which practically no class needs).
Highmountain tauren - "Descended from Huln, brave hero of the War of the Ancients, the Highmountain tauren honor the spirits of earth, river, and sky. Though the Legion invaded their lands and sowed seeds of distrust between them, the tribes of Highmountain stand united once more. At long last they are ready to venture beyond their sacred mountain and stand beside their kin from Kalimdor, lending their nobility and strength to the mighty Horde."
Most of the players make the mistake of only listing 30-50 transmog items on the auction house and then hoping to get half of them sold until the next day. Me and a lot of other gold farmers and transmog sellers do have 3.000-10.000 items on the auction house across various realms. It does not mean you have to do it that way – but if you have 1000 items listed, chances are higher you can sell up to 10 per day. With only 100 items listed, you have to be lucky to sell one. Of course, the sells are not guaranteed if you post more items. But i’m sure you have a lot more fun if you open your mailbox and 10-20 items are sold