This top-end difficulty was missing entirely from Legion’s first raid, Emerald Nightmare, which was cleared by top guilds in around 11 hours. Meanwhile the first guild to clear Uldir’s hardest difficulty, Mythic, spent somewhere around 70 hours attempting to kill the raid’s eight bosses. Even after all that time, the guild, Method, still had members say they loved the raid, and that it was one of their favorite in recent memory.
The Auction House is always the best option for getting good equipment at a good price. The only items you should be buying from Vendors are basic consumables: food, drinks, arrows, bullets, vials, dyes, etc. Most other things should come from the Auction House, as they are generally cheaper. Keep these tips in mind when buying items off the Auction House:
Only really to expand on Gráinne's comment as regards the 'collecting' and 'roster development' sections - which are, as said 'distinct' although they are intrinsically linked - I would like to point you in the direction of the in-game Achievements > Battle Pets > Collect tab. There are a series of achievements called Raiding With Leashes, pretty much all of which can be completed via the auction house - if you have the gold/inclination - or by completing old raids.
Swim Speed Potions (used especially at lvl 37 for Faldir's Cove in Arathi Highlands and lvl 57 in WPL). Try to get multiple stacks of these. I also recommend keeping a stack of these always in your bags. You will frequently pass rivers and lakes and can use these potions to pass them faster through out the guide. Please note that these potions do not stack with Druid's Aquatic Form and Glyph of Aquatic Form.
Repetitive daily quests are a legitimate method of generating significant cashflow. Players who spend several hours a day doing daily quests can often generate 100 per hour. Many players have funded the purchase of their elite flying mounts solely through doing daily quests. Another trick for higher level players is to do level 70 dailies as a level 75-77. If you have a hankering to get a Netherdrake, for instance, and you already have a fast flying mount (which is a pre-requisite for the drake), you will find your mid-70s an ideal time to go get that drake. Not only will the quests be a lot easier to do at level 75+, but the dailies will pay about 1200 as you level rep, and you'll get XP along the way to boot (albeit not as much as quests in Northrend.) So if you're looking for a break from the grind of leveling to 80, and want to kick back, spank some level 69s and make some decent money along the way, doing lower level dailies can be a fun way to make some extra cash.
Two new raids coming after the initial update differ drastically in size and content, depending on which side of the war you’re on. The Battle of Dazar’alor raid sees Alliance players trying to take over a city, but if you’re part of the horde, your version will see you try to defend it. Once you’ve beaten it once, you can then play the other side. The Crucible of Storms raid, on the other hand, is smaller and only consists of two bosses.
Once your character makes it to Outland and beyond, cashflow frees up considerably. The quest rewards are much better than in Azeroth. In fact, a typical character will earn from 1000-1200 in quest rewards and vendor trash while leveling 60-70 in Outland, and perhaps 1400-1600 from 70-80 in Northrend. The tendency is, therefore, to spend more freely after one hits 60. However, it is important for players not to go crazy on their spending once they make it to Hellfire. One thing is, training costs, repair costs, and consumable costs are also higher. More important, there is a large purchase that you are going to want to make at some point after level 60, your first flying mount and skill. The "bird" costs 40, the skill will cost you far more. Not only that, but if you want to fly it in Northrend at level 70, you'll have to shell out another 400 for Cold Weather Flying. And for those characters who will be 'farming' herbs or ore in either Outland or Northrend, an elite flying mount is almost essential, as it helps you gather almost twice as fast. That's another 5000 you'll be looking at. Therefore, budgeting carefully during the 60-80 leveling process is essential to ensuring you have sufficient cash on hand for making those purchases. Saving your pennies early makes that bird appear that much sooner.