A Baker's Dozen of WoW Gold Tips

This in an ancient, out of date, page that is kept here for legacy sake.
Click here for a more up to date Gold Tips page.

And now, back to your regularly scheduled guide:

Introduction

Ok, you've got 6 figures in your gold account, you're decked head to toe in epics dropped off the Auction house, or bought through contracted guild raids, and you have every pet and every mount. You fully find your stable of 85s and your guild looks to you for all their running money. You don't need a gold guide, you should be writing one. Now go away and get back to work.

This guide is for the other guy/gal who has problems scraping up enough to meet expenses or who would like to buy their epic mounts and flyers. While I do recommend a couple of gold guides (they cover different areas) those are only for people who are serious about playing the gold game. Want to make 100k gold? Get Zygor. Just want to make enough to meet expenses, get your mounts, and some decent gear? This page will be enough.

Gold and More:

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The Three Sources of Gold Aquisition

Basically there are three ways to get gold in the World of Warcraft (and pretty much any other video game or MMO) and that's to complete quests (and kill mobs,) sell stuff to the vendor, or sell stuff to other players. While there are a few other bits where you can grab some cash (such as opening chests & boxes) those three areas cover 99% of the gold accumulation that you will ever do.

While quests and vendors are pretty clear, selling stuff to other players involves gathering stuff that they might actually want to buy (and pay a lot of money for.) Some of the items that you will (or could be) gathering or creating for these sales are:

Mats for enchanters through disenchanting of items
Finding materials for cooking and other crafts: cloth, skins, ores, herbs for the crafters: Alchemists, Scribes, Blacksmiths, Leatherworkers, etc.
Farming more exotic items for crafters, such as motes, crystallized this and that, Volitile whatevers, and so on.
Vanity items, such as wedding dresses, hats, tuxedos, name brand gears, etc.
Farming items from mobs, such as weapons, rep items, etc.

Piles o' Stuff Vs One-Offs

One of the things that effects the price you can ask for an item is how people actually buy that item.

Things like ores, skins, rep items, herbs, etc tend to sell in stacks and will have repeat customers. Things like crafted items don't sell in stacks (even if they're stackable, like Glyphs) and repeat customers, for the same item, are rare.

This becomes important when you're posting your items on the Auction House (AH.) A scribe or Leatherworker might pick up a dozen (or more) stacks of raw marerials at one time, and come back for more later, so even if you don't have the lowest price your items will sell (assuming you're not crazy high with the price.)

Any given character will only buy one each of any given crafted item. So when putting these items up for sale there's more incentive to have the lowest price on that item. This is why you will see all the glyphs sellers constantly undercutting each other. As a seller of materials you don't have to play the undercutting game.

Even if the current price for raw materials is low, at the moment, you will still sell your stuff if you price higher. Look at the AH over the week and you'll see the prices vary. Keep your prices a little higher and you'll make a lot more in the long run. If stuff is priced too low then either wait of buy it out to resell later.

Ok, Let's Get Started with the Tips

Roll yourself a dedicated Auction House Banker. Everytime you stop by town to lighten your bags you can mail the worthwhile stuff to your banker and then get back to work. The banker will do all your AH selling and buying, freeing up your other characters to do whatever it is that they do.
Buy the biggest bags you can afford, eventually working up to those 20 slot Frostweave Bags. Go for the 22 slot Glacial Bags if you can (and think they're worth the price.) Do the same for your banker. This will minimize your trips to town to unload stuff and maximize your collecting time. Your bank also has bag slots. When you get to the point that you're banking stuff you will buy those slots and stick frostweave bags in them.

2a) Have your alt create a guild (paying 10g for each signup,) then kick everyone, and use the guild bank space for your stash.

Loot everything, always. Vendor the gray stuff and send all the white (and better) stuff to your banker. If you're high enough level you can solo instances, looting everything, and make a nice pile of gold selling the grey titled stuff to the vendor and the better stuff on the AH. You might even find some nice blue (and maybe even purple) items that you can sell for a high price.
White items sometimes sell at a surpisingly high price. Always check out the current prices on the AH on these items. For example, the Farmer's Broom and Farmer's Shovel are low level white weapons that are good for low level PvP and they sell for several gold each. Bits used for crafting might also sell very well. I remember being quite surprised at the price that the "large fang" sold for. Believe it or not white armor and gear actually sells on the AH. Not for a lot, but definitely for more than a vendor will pay youi.
Grinding and Questing: If you're going to grind mobs in some area see if you can pick up the appropriate kill quest(s) or quests that are in the same area. You'll get the quest reward and the occasional items when completing the quest in addition to whatever you get from the mobs.
Any of the gathering skills (mining, skinning, herbalism) will keep you in the gold if you work them. Try and keep them maxed at all times and never pass up a node, plant, or skinning chance. We recommend Skinning and either Herbalism or Mining. Why? You're going to be killing a bazillion critters while you level anyway, so why not skinning?

If you're a skinner then skin everyting you can, always. Sometimes other players will kill skinnable mobs and leave them there. Skin 'em yourself. Sell the scraps, too.

Keep in mind that the Skinning skill gives you a smal crit buff, Mining adds Stam, and Herbalism a small heal.
Cloth always sells, though you should check prices. (Also look at the deposit costs, the Runecloth deposit is far higher than that for Wool Cloth.) One day prices will suck, a few days later they'll be better. Also consider stashing the cloth to level up your first aid and that of your alts. Some types of cloth can also be turned in for rep rewards. As you know, the cloth type dropped is dependant on the mob level. Hit 25ish (humanoid) mobs for Wool Cloth, for example.
Limiteds: You may have noticed that some vendors sell items in strictly limited numbers. These limited items often sell for a lot more on the AH than it costs you to buy them. Always keep an eye out for these and make a note when you find interesting limited items.
Some green items will sell very nicely, others just don't. Who wants a 2 hand sword with a Spirit buff, after all? You should disenchant green and better items that don't sell and then sell the parts. If you have a stack of green items and don't have Enchanting then you might be able to sell them to an enchanter so that she can disenchant them. You can also work your banker up to level 10 and get Journeyman Enchanting. That will allow you to disenchant things for awhile.
Daily Quests: Starting at 70 you can do the various daily quests. These pay gold, of course, and sometimes rep and various items. If you are grinding rep with certain factions you will definitely want to look into the dally quests. There are plenty of daily quests in the new Cataclysm areas and these also provide rep to use to buy some very nice gear.

The trick is to grab several of these quests that are in the same area or easily follow one into the other, otherwise you spend too much time traveling. The Isle of Quel'Danis or Tol Barad quests are perfect for this. You can do the 10 quests in about an hour (once you have the routine down) make a nice pile of gold, get rep, and get a stack of stuff to sell to the vendor and AH.

Unlike some other daily quests you don't need a flying mount to do these. The level 85 quests are similar. You won't make as much from dalies as you will from efficient farming or Auction House games, but if you want the rep and/or don't care to play the AH then go for it.
Pricing: Remember, with cloth and the stacks of stuff you gather (including enchanting materials) you do not have to have the lowest price. Peolpe buy piles of this stuff and come back for more, so don't shoot yourself in the foot by pricing it too low. Price your stuff a couple steps higher than the lowest priced stuff, it'll still sell. Heck, if some goof puts up a few stacks at a way low price just buy them all and repost them (now or later) at the right price.
Addons: If you're a miner or herbalist you should grab the Cartographer and Gatherer addons, from Curseforge, along with the WoWhead database that comes with Gatherer. This will give you a map of the common locations where ores and herbs appear and will make your gathering faster. (Note, the new WoW quest tracking system doesn't play well with Cartographer as of this writing.)
An addon like Auctioneer (free) is really valuable, though some recommend other addons. The idea is that it will give you pricing info so that you can price your items correctly when you post them on the AH. With this info you will know if the current listings are too low (and you should wait) or too high (post now.) Curseforge.com has a couple of other Auction addons, as well.

Bonus Tips for More Gold:

Figure out what mats are needed for specific items, then farm those mats. For example, if a particular potion is in great demand (perhaps for raiding) then farm the mats for the alchemists to make those potions. Check WoWhead.com for item requirements.
Have a "shopping basket" of items in your bank alt's bags. Then scan the AH for those items, byuing up what's uderpriced (for reposting, perhaps later.) For instance you might have a "basket" containing one of each herb used for Inscription. Open the AH, shift+click each herb in turn (shift+click posts the name of the item in the search field,) and hit search. Buy up what's appropriate.

If youi find that no items are available, and you have stored a stash of same, post them at a (reasonably) high price. You'll have a monopoly (for a time) and should do well.

The Auctionator addon will let you create shopping lists so that you don't have to keep stuff in your bags.
Specific crafted items require specific quantities of mats, so sell you stuff in those quantities. For example, Scribes mill herbs 5 at a time, so if you're selling to Scribes sell your herbs in stacks of multiples of 5. Or if Potion AbC requires six green pointyflowers then sell your stash of green pointyflowers in stacks of six. Again, check Thottbot for stack sizes.
Make the intermediate parts for crafters. Scribes mill herbs into pigments, then inks, then glyphs. So, if you have Inscription & Herbalism, you can farm herbs, make inks, and sell the inks. Check your own server's AH prices, you may find that a 5 stack of herbs sells for more than you can sell the inks, or visa versa.