The greatest potential for going from 25,000g to the gold cap of 214748g is transferring servers. However, this also presents the greatest risk and needs the most preparation. First off, transferring costs money. If you go to a server, transferring back as soon as the cool down is up is expensive and impractical. You should look for a server that you can stay on for at least 6 months to a year before transferring back with your huge profit. However, the maximum amount of gold that a max character can transfer is only 20,000. Therefore, you need to purchase goods that are going to net you the most profit when you go to sell them on the new server's auction house. Primarily, these are enchanting mats, but can also be BoE epics depending on the two servers. Before making a risky decision such as transferring, consult the questions below.

Update: The reason for less experience from gathering is due to how Blizzard revamped professions and broke them down by expansion. In order to get full exp from gathering you'll simply need to find a profession trainer for the relevant expansion. (WoD you just mine or herb the first one ypu come across and the game gives you a scroll for learning WoD gathering).
These books cost 1.000 Gold each and are sold from your BfA gathering profession trainer. As soon as you re-learned your farming profession, use this book and you will get back all of your lost Battle for Azeroth gathering ranks. Your gathering skill remains reset at 1, but you don’t have to care about that since you have your ranks back – thats literally all that matters.
Icy Veins Podcast Episode #39 We're back with a brand new episode of the Icy Veins Podcast, where we talk with Deadset about Diablo's upcoming Patch 2.6.5 and Season 17 that wll be available for playtesting for a week starting Friday and we also cover what's coming in World of Warcraft's next major content update, Patch 8.2. Icy Veins Icy Veins Apr 03, 2019 at 20:22 by Stan
Don't put all your eggs in one basket. It's a lot better to spend your working capital on buying forty items for auction, each with the potential for profit, than to take all your working capital and invest it in that one purple leatherworking recipe that you hope will make you several hundred gold. If that puppy doesn't sell, or doesn't sell for what you want, you've just wasted all your working money, and deprived yourself of a lot of flexibility. Leave speculating on purple items until you have a few thousand gold squirreled away.
Mechagon and Nazjatar will both be endgame experiences that draw on the best elements of previous endgame grinds: the Timeless Isle, Argus, Tanaan Jungle, and the Broken Shore. Azshara’s domain of Nazjatar will be a little more typical, while Mechagon will be “what you might expect from a gnomish paradise,” says Hazzikostas. He describes it as more sandbox-y, unpredictable, and akin to a playground. Both zones will have flying enabled.
Some players even turn this into their profession by systematically "plundering" vendors in the game world and then selling the items on the auction house at a significant markup. The reason why this works (even for items which are on unlimited supply at vendors) is, that many players don't want to spend time traveling to specific vendors to get hold of a recipe or skill book. They would rather pay a slightly higher price at their local auction house. In some sense, they use the auction house as a "super market" or "convenience store". So it is completely reasonable and legitimate to be the supplier for this convenience store and make money out of it.

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.
Through out the game, the quest log will be capped to 20 many times.  The guide makes use of maximizing the total amount of quests you can accept at once.  Because of this it is important to follow the guide exactly and only accept quests if the guide tells you to so you won't run into issues not being able to accept a quest.  If you do accept a quest that is not listed in the guide, write it down because you may need to abandon it in order to keep following the guide if your quest log is full.
Gold for riding training. Travel time is a SIGNIFICANT time sink while using quests to level. You don't want to wait to get it. In fact, while questing, the second you ding 40/60/70/80 you'll want to hearth and train it IMMEDIATELY! 10304 gold is the base cost, which will be modified by reputation. Also, make sure you're in a guild with the 10% riding speed bonus unless you're a class that already gets a mount-speed buff. 

For instance, Horde players see their story through an oppressively dark light, and it’s easy to see why. The Horde exclusive content — the War of the Thorns, the end-game war campaign, and the Darkshore quests and warfront — is all focused on killing, blighting, burning, betraying, and raising people into undeath. Yet canonically, the Horde is the one who stopped G’huun in Uldir and saved the world. The Alliance had access to the exact same content, just with less lore and story. The Horde players don’t get the balance of feeling like they saved the world, because it would mean Alliance players would sit on their hands for months watching the rest of the players advance.
Just before Battle for Azeroth goes live, you will want to log all of your characters out in the zone of Silithus so that you can acquire the quest to talk to Magni and obtain your Heart of Azeroth (refer to our Heart of Azeroth guide for more information about this item). This is the new artifact-type of piece of equipment that you will use for all of the Battle for Azeroth expansion. Once you acquire your permanent neck slot piece of equipment, get back to Stormwind or Orgrimmar to begin your scenario that leads into the introductory areas of Kul Tiras and Zandalar.
You are right here. The Rematch string is part of the Info box, and as such it should be parsed correctly. (The string that contains the correct and breed/damage-specific min health requirements). This should be enough, but, I think there are also folks that aren’t using Rematch. They also should know of the type-specific min health requirements. Unfortunatly the default forms of the page don’t offer any detailed entries for the min health. They only offer one entry (for all damage types), and I always put the worst-case min health there (for pets that are weak against the expected damage type)
NOTE: It is VERY important to not vendor any equipment you pick up. You will be deconstructing all of your gear for resources that will help you in the Warfronts to be fought! Deconstructing, or scrapping, your gear will be done using the Scrap-o-Matic 1000 if you are Alliance and the Shred-Master Mk1 if you are Horde. This works the same as the way the Obliterum Forge worked in Legion. The scrapping feature can be used on all Battle for Azeroth equipment found, not just craftable equipment, so save everything you acquire for the scrapper! Before we get started, keep in mind some of the tips below that can speed up your leveling process!
Mists of Pandaria has a few rare mobs that drop epic BoE’s. Most are in Krasarang Wilds and most drop leg slot gear. Scritch is also very good as you can get the Hozen Peace Pipe from him. The best way to farm them is to occasionally check if they’re up and kill them all in the order listed below. That way you basically just fly through Krasarang Wilds with a short visit to Townlong Steppes, The Jade Forest and Kun-Lai Summit

I'd say level this toon a bit more, maybe up to 30 or so, and see how you like the experience. If you find questing just a means to an end, maybe the guide would be a good buy. Me, I generally like questing and go to an area I'm interested in, even if it's not the most level-appropriate for me or the best way to maximize my time, so those guides aren't of much interest to me for now.
Both Burke and Danuser repeatedly stressed throughout the course of the interview that the Alliance is not a monolith of views and approaches. However, one character has taken the spotlight and the reigns of action: Anduin, the new high king. “With the death of Varian in Legion and the rise of Anduin to Kinghood, we’ve spent a lot of time on his character and showing his growth,” says Danuser. “He’s a great character, and we wanted to show how he interacts with big figures in the game.”

World of Warcraft: Battle for Azeroth also provides you with the opportunity to quickly upgrade your character to level 110. Enter the enormous battle fully prepared for it. After you start the expansion, you will sail to the kingdom of Kul Tiras and visit the trolls of the Zandalari Empire. Win epic battles and take control over the strategically placed Stromgarde. Discover a twenty-player cooperative missions on the War Front and take part in numerous expeditions. Gather resources scattered over treacherous, undiscovered territory.

Finding the best route for you can be a bit tricky because of the size of the dungeon. I will usually only do about half the dungeon, killing as many mobs as I can in 6 minutes. After 5 minutes, make a group in the group finder and leave it. That will leave you a minute to complete your 6 minutes and you will be ported out on the 6 minute mark, ready to reset and port right back in.
Heirlooms can certainly be used with our guides! You may find yourself getting ahead of the guide. If you start doing gray quests, just skip ahead to a later zone. The guide is just that - a *GUIDE* not a rule, as many people seem to think. Feel free to skip parts! Watch out for quest chains, though, especially in the last part of the 50-60 section. Hopefully we'll have some awesome features in our new addon that will make it easier to skip around!
The most rare and expensive poly morph tome drop and for a reason.  The bears that drop it are VASTLY spread out across the zone and getting one can mean hard farminh for a while.  They also take a while to respawn so watch out.  Getting one to drop can mean a staggering 48,000g, and on top of that compared to other pet farms and such, they have a much higher drop chance.  Simply head over to dragonbligh ona mage character (class trial is perfect) and start the killing.  Cross you fingers as there is an 0.4% chance to get one on each kill.  Thats actually pretty high considering..
This farm almost did not make the list, since every YouTuber and farmer alike has beaten it to death since it first appeared sometime in 2012.  There are so many videos on this spot, that it's hard to to stumble across one, even while searching for something completely mundane, like chicken wings or golf clubs.  Anyway, you want to pull the entire instance without aggroing any of the bosses, and if your a skinner you an make slightly more gold by skinning the hides.  Generally this farm is being phased out by the lvl 58 twilight outpost farm, and with good reason.  It's better and does not require you to enter the instance.  So more drops for you!  Not sure, why anyone would pick this spot over the latter unless you were really interested in increasing you skinning level.

The Heart of Azeroth is an artifact given to the player character from the world soul via Magni Bronzebeard. It is a necklace that can use the power of Azerite, the lifeblood of the embryonic titan Azeroth (See Plot, below). Azerite is similar in function to Legion's artifact power, in that it is gathered normally from playing the game and is used to upgrade an artifact; likewise, the Heart is similar in function to Legion's artifact weapons by having the capacity to be constantly upgraded. Unlike artifact weapons, however, the Heart is shared with all of the player's specializations and can empower all eligible pieces worn simultaneously.
5% was admittedly an exaggeration, just felt that low. I'd say it was probably closer to the 30-40% range. It was Artifacts of the Blacksilt, spent a good 10-15 minutes killing Blacksilt Seers to get two damn idols to drop. A quest that had me killing Elder Brown Bears for bear flanks also took quite a while, though that was less due to drop rate and more due to how spread out they were.