Cataclysm brought several new collectable pets, including Engineering’s Personal World Destroyer. If your Engineering’s high enough, I recommend grabbing it and start production. Not everyone has Engineering that high, if at all. So, instead, let’s focus on three cash generating pets that can all be learned by 205.
The first is the Mechanical Squirrel. Not only is the recipe (Engineering 75) easy to find on the Auction House, or possibly from a trash drop, but the mats are dirt cheap right now thanks to the influx of new characters and professions. Essentially you need Linen Cloth, Copper Bars, and Malachite. Really, Copper’s the only thing that might drive up your materials cost, but you should still be able to make a half dozen or more for about 10g. You should then be able to sell each one for 5-12g. Again, financial mileage may vary, but this is easy money.
The Pet Bombling and Lil’ Smoky are harder to obtain, as they’re both BoP. Now, the Bombling is a guaranteed drop from Mekgineer Thermaplugg. Smoky simply has a decent drop rate from several of the mobs in the instance. The one thing to know from these pets, is that you need access to Fused Wiring. It’s a 275 recipe, but there’s usually some on the Auction House at a value that won’t kill your profits on these guys. Speaking of profits, they’ve provided their makes a flush of gold since Cataclysm thanks to the abundance of Mithril in the world. Whether you farm it, or simply buy it for a decent price, it’s far easier than it was to get pre-Shattering. These two pets are 75-125g for the most part and it will never cost you half that to make them.
So, let’s presume you’re on an average server with an average economy. You make two of each a day. Six pets, with an approximate return of more than 300g. Pretty good, isn’t it?
Now, if you wish, you can increase your Engineering to 250 and learn the Tranquil Mechanical Yeti. Just keep in mind you need to be level 55 to knock off the quest chain that grants the recipe. That makes it far less appealing.
As for the Lifelike Mechanical Toad you can learn at 265, that’s a tough call. For starters, the recipe itself is worth several thousand gold on certain servers because of sheer rarity. Can you make money from making the pet? Certainly. Unless the Schematic falls in your hands, you’d have to decide whether it’s worth it. Then again, even if it dropped for you I would put some thought into said decision.
As you can see, there’s a few pets at higher level Engineering that you can profit from, but the three low ones, even the lowest one, brings enough return that if you’re just in it for the money you simply don’t need to level any higher.