I can't really encourage anyone to level a craft, myself. Whatever markets may exist at the moment are likely be dominated by those with 110+accessories, with further profits likely hinging on hoping for HQs. You'll simply be bleeding lots and lots of money just to even get to that point, when you probably could've just spent the same time farming RME currency or something and coming out way ahead. And depending on the craft, that 100-110 push can be awful even with skilling up over level now possible.
I can't say I agree with this, though to be honestly. There are some cheap and easy things to get to, that you can do it over time and it won't cost you a whole lot.
How about Garudites and the other avatar rocks? I get a lot of them. A ton of them. They don't really sell well on AH last I checked, they vendor for 200-ish gil.
BUT if you cut them, they vendor for 2,400. That's 10x the value. You need ~Lv70 goldsmithing to be able to do this, though. However, if you're willing to spend a little start-up capital (you'll make it back, easy), you can get up to Lv62. Getting from 62 to 70 is the worst part of it, but with a little patience and lots of Mog Garden use, and/or a little money spent, you should be able to get there especially if you use the 5% skillup foods.
But once you do, those rocks add up rather fast. Every time I go out to fight stuff, I usually end up with 20, 30 of these rocks and at 2400gil a pop, those add up over time. Also, now that my Goldsmith is just shy of Lv95, I can make Rhodium Ingots. These sell on AH for 140k per ingot and I'm still skilling on them as an added bonus. The Rhodium Ore comes from my Mog Garden. You also get Platinum Ore and Orichalcum and 12 O. Ingots go for 400k. Over a month or so of building up materials, I sold 1.5 million gil worth of ingots on the AH.
Also, Woodworking. Some logs don't really sell all that great on the AH, but they are worth more to NPC if you cut them into lumber. Some lumbers aren't too bad either.
You only "bleed lots and lots of money" if you do it stupidly. I have ALL crafts at Veteran, and 3 of those just became Veterans within the last month or so, but I've hardly spent any gil at all (the worst was 500k in Iron Chains for my Leatherworker... annoying. Why'd they make Iron so annoying?). But yet, he'll make a chunk of that back when he vendors the belts he will be making, and he'll make even more back when I vendor the Aetosaur Gloves I'll make when he's high enough.
Also, my Cook got from 100 -> 106 for free. In fact, mild profit. 3 sandy carrots at 28gil each makes 4 jugs that vendor for 76gil each, IIRC. lol. The recipe also calls for verboshroom, but I had 200+ of them from grinding away in Cirdas Caverns.
The game throws a LOT of junk at you, and you can just use the junk you get to level crafts up and/or find cool combos to do to vendor to NPC. But, you can't craft anything if you don't level any crafts.
EDIT: Also, to get my woodworker on... 105? I think? I spent 50k per stack on Kapor Logs. Turned them into Lumber for "meh" skillups, and then combined them with Black Chocobo Feathers to make Wands. Said wands vendored for about 3k, so... ~60k on logs and feathers, ~35k back from vendoring wands. Not too shabby.
Edited, Jan 11th 2017 1:57pm by Lyrailis