So, this isn't a guide - but a few pointers that I felt like sharing. Mostly, because I get asked this question a lot on my server, and I'm going to just macro a link to this thread. This may not work on your server, dependent on your servers' economy. So no, "On my server, this doesn't work" please. This is meant to be an over-generalized starting point for beginners.
10 Techniques to strike it big with Engineering in 10 minutes or less a day.
(1) Download Auctioneer.
(2) Never list for 48 hours. Only list for 12 hours. Always. 90% of the time, you will be undercut within 12 hours, making >12h auctions useless.
(3) Shatter Rounds > Icefall Arrows
- (a) Dwarves have + crit % to using guns, so long-term bullets will win.
(b) All the really good ranged weapons seem to be (x)bows, not guns. So demand is significantly lower. However, most engineers are hunters (to supply their own arrows), or intuitively went for arrows due to the slant of (x)bows Vs. guns. This means that competition in arrows is excessively high. (Example: Cenarian Circle :: Arrows (<5g /s) Bullets (9-12g /s)
(4) It's not about controlling, or manipulating the market on Bullets. It's about riding it. Always look at Saronite/Eternal Earth/Thorium* (Re: Pets), even if you have plenty. If you see it cheaper than normal, stock up. You'll be able to keep your business going when during the inflation phase(s) of raw materials because of this.
- Too many people try to control, or excessively manipulate, the market. You'll lose your ass if you have any sort of competition against you with more free time than you. Don't try to control it, or else buckle down for a lot of work. Simply post a few copper lower than the lowest price every time you list.
(5) Do not merely buy up your competition, ride it out. However, to avoid the market bottoming out; let the value of the ammo reach ~40% of it's normal, then buy the competition, and re-list it. You may not sell them all @ 100% Market Value, but you'll make your money back from the investment, and your (personally made) rounds will sell for more.
(6) Never list more than 30,000 Shatter Rounds, and never retain more than 50,000 Shatter Rounds on your person.
(7) When you exceed 50,000 Shatter Rounds in reserve, open up Auctioneer and see who your most frequent buyers are. Send them an in-game mail, containing 10,000 free Shatter Rounds. The investment may be wasted or it may have excellent returns. However, 10,000 Shatter Rounds isn't excessively expensive - so the risk is low, and gain is potentially high.
- (a) Contain in that e-mail some excuse -- I made too many; or I got lucky on selling a few choppers and felt like being generous.
(b) Also contain in that e-mail a friendly, but not pushy, offer of bypassing the Auction House, and have them mail you a REQUEST (NOT MATERIALS) for XX,XXX Shatter Rounds whenever they're needed at 80% AH price. (This will bypass Auction House fees, and cut for you, resulting in only about 5% loss. This will also, should they take you up on your offer, bypass any potential loss of income due to competition undercutting you at inopportune times) -- TL;DR = -5% income for you +20% income for them.
(8 ) Be honest, always. Never attempt to sell Shatter Rounds for more than 30g/s - never less than 6g/s. Never try to deceive, or rip off, the people who work with you via mail.
(9) Choppers: Come up with a catchy jingle to help sell it. Become an icon in your community. If they think of choppers, they had better think of you. Never, under any circumstance, AH your salvaged chopper parts. Retain them for personal use, or commercial use. When individuals buy a chopper for 12.5k + mats, sell them a salvaged part in lieu of vendor part. This will cause you to receive the full fiscal benefit of the part; rather than selling it on the AH for ~80%.
- (a) In addition, search the AH for vendor parts before making a chopper for the same reasoning.
(10) Pets: Pets are tricky. They're only worth what people pay for them, and people will only pay so much. Periodically check (especially during the weekend) on materials such as "Globe of water" and "Thorium", and keep a keen eye on trade chat for lowbies "LF places to farm Thorium". Swipe them up when they're cheap, and convince the lowbies to sell to you for wholesale prices what they don't need. Only make pets when the mats are at or under 30-50g each.
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For those wondering: while using Saronite/Thermal charges every GCD on a 28 hour raid schedule, as well as speed pots per boss, flasks, elixirs, and BiS food for tanking and DPS; leveling an alts' riding skill/professions; I maintain 8 to 25kg without dailies/farming, and spending only about 7 - 12 minutes a day on the AH. So, while it may not work on your server, it seems to work on mine.
Anyhow, take it, hate it, whatever!