The most simple thing is TradeSkillMaster. This AddOn shows you quite an amount of information in the items tooltip. In my opinion, DBRegionMarketAvg the best source. It tells me the price, an item was posted on all EU realms in the last 14 days. Why not DBMarket? DBMarket only shows you the items value from your server in the last 14 days. This value often gets manipulated. Some people start to post an item with a 500g value for 500.000 Gold on the auction house for several weaks. As a consequence, DBMarket is rising towards 500.000 Gold.  If you use DBMarket with 100% and post your item for 500.000 Gold, nobody will buy it.
Always post a buyout price on your auctions. Don't think that "They'll just bid it up anyway." Many players will not bid on an auction with no buyout price unless the item's bid price is heavily discounted to begin with. This can lead to bidding wars, but in many cases the item will sell for a fraction of what you could have gotten if you had posted a buyout price in the first place. You will have more sales at a higher price and get your money more quickly if you post a proper buyout price.

With Mining, from the moment you take the skill you can make good money selling stacks of the bars or ores in the Auction House. Blacksmiths, Engineers and Jewelcrafters are interested in the bars, while Jewelcrafters and even other miners may want to buy the ores. Make sure to check the relative prices of ore versus bars before smelting. As your skill increases, so does your earning potential. At the maximum level you may smelt Titansteel for a daily fee.

Each of those modes existed long before this latest expansion; raiding is a basic concept in MMOs, and Mythic+ was added in World of Warcraft’s last expansion. The problems with Battle for Azeroth’s endgame come from the systems it adds, which most often artificially gate progress where most of the fun can be found. If raids and Mythic+ are the carrot, we’re about to talk about the stick.
Mythic+ has some similarity to raiding, but it’s designed for just five players, instead of the 10-to-30 that can make up a raid. This mode tasks players with clearing the game’s dungeons, but with specific changes that make them harder, scaling up until it’s impossible for groups to finish. Players receive a keystone in their inventory that assigns them their dungeon, one of the game’s 10, and gives the dungeon a level. This determines how difficult enemies are and what effects might make them harder. If the group completes the keystone in time, they get a new, higher-level stone; if they, don’t they get a lower-level stone.
World of Warcraft offers a lot of ways to make money (gold). There is no one "right" way to make money, although there are some definite wrong ways! Some people like to play the Auction House, some people do their daily quests, some people tend to farm, etc. Many characters do a combination of all three of these along with other activities. Below is a compendium of money-making methods.
Once you get to about 200g, the theoretical limit of your profit virtually disappears. You now have enough money to start mass buying and reselling those players' goods who undercut everything by an extreme amount. Enchant mats are still a very good focus during this period, especially essences and crystals. You can now afford to buy several maelstrom and abyss crystals and wait until prices fluctuate to resell for a profit. A major strategy you can begin to employ is the multi-character trading and auctioning. If you come across 5 abyss crystals, get onto one character during peak hours and advertise a price 25-50% higher than average. When no one responds to this, quickly switch to another toon and offer the same 5 crystals for 10% lower than before. This will help to raise the median price because other sellers see what they may be able to get for their good. While they are cancelling and reposting, take this time to undercut their new prices, which is now more than you ever could have gotten before when prices were low. If you master this with BoE epics or more rare items, then you can make differences of thousands of gold.
Battle for Azeroth has struggled to find a similar role for the player character. The Alliance has largely served as a foil for the Horde. The Horde, on the other hand, are dealing with a deep division. Horde players who do not agree with Sylvanas were given the option to choose a route of defying her ... but this comes after they were made complicit in genocide. It’s not the burning of Darnassus that motivated them, but the follow-up decisions by Sylvanas. 

Skinning is both highly profitable and convenient, in that you will be skinning the monsters that you're already killing as you level. A skinner starts by collecting relatively worthless ruined leather scraps, but soon moves on to light leather, which can be sold for a good profit. An excellent way to farm leather is to skin the kills of other players, especially if you are following along in the wake of a group. However, do wait to start skinning until it's clear that the other player has abandoned the kill. Don't assume that the other player doesn't skin just because they are not a leather-wearer, for example. Note that your chances of getting a better grade of leather increases with your experience; it is possible, though rare, to get light leather from rabbits. Higher grades of leather yield higher profits. A skinner/miner has potent earning power through the auction house, but often runs out of inventory space.
Whatever your approach, if you use some common sense and apply yourself, you can make significant quantities of money in the game. By managing your cashflow, conserving and budgeting where you can, and investing wisely in those activities that make you money, you can become financially solvent relatively early in your career, and remain comfortably well-off (while still buying good gear) at level 80. Good luck!
Heirlooms are special pieces of armor that level up with your character, so they have stats that are always respectable for your character’s level (up to level 110). Heirlooms that fit the head, shoulder, chest, legs, and back armor slot offer an experience bonus. The total bonus is 45 percent if you have them all. It’s also possible to acquire a ring that adds another 5 percent, but you must win a fishing contest acquire it, and that can take some time.
Before you begin, you must decide on whether or not to enable War Mode. War Mode makes it so that you will only see other players with War Mode enabled, which also enables PvP activity. Note that if you are in a party with someone not on War Mode while you are, you will be unable to see him or her. War Mode provides an experience buff as well as the enabling of three PvP talents that will greatly increase your power. Regardless of whether or not you enable War Mode, your objectives will remain the same in that you must complete all quest content to unlock flying later on and many of your War Campaign and Allied Race requirements. War Mode enables 10% bonus experience, 10% better rewards from World Quests, and allows for the gathering of Conquest points which can be used to buy gear. If you do play on War Mode, it is recommended to play with friends. Leveling without War Mode will not be significantly more time consuming.
Always updated: Zygor‘s is completely updated for the 5.4.2 patch and will be for all subsequent patches and expansion, including Warlords of Draenor. You’ll be able to do the blast to level 90 (and later, 100) in very good time and get into all that good end game stuff. It does this with an easy to use updating widget so you will always be up to date.
Combat is turn-based and there is no time limit on each round in a PVE Pet Battle. You can take your time to determine which spell to use next. Some pet abilities have multiple round cooldowns, while others can do extra damage if certain conditions are met. Be creative and have fun testing which combination of attacks works best against different wild pets!
When it comes to gold making addons, as most of you know, there is one that comes before all the rest, Tradeskill Master. This addon will help you make heaps of gold on the auctions house, and will give you a deeper understanding of your servers economy and the whole WoW economy. Learning how to use it well takes time, so read through all the info on their site and maybe watch some youtube videos on how to set up TSM. TSM will help you appraise items, sell items quickly on the AH and buy items that you can resell for a profit, amongst other things. Additionally the addon will help vendor and managing your mailbox, making this the only addon you need for gold making purposes. We will be coming back to TSM in the Auction house part of the guide. 

-Gameplay- Gameplay has largely been stripped down to be a shell of its former self. This trimming has been going on for several expansions, but now it's even worse. Classes only have so many buttons which has resulted in very little skill involved in PvE (even PvP is a faceroll for most melee, lacking any sort of depth and decision-making as it's pretty clear what buttons to press in any given situation) and it's become more of a gear check. This expansion gave zero new abilities to classes, only took them away.