This has been my personal method to slow, but virtually guaranteed, wealth:
[*]Buy uncommon set recipes from the market at level 20 (to minimize crafting fees), that have ZERO rare salvage to craft. It doesn't really matter what it is, as long as it requires no rare salvage. I usually pay about 3500 for each piece of salvage, because I'm impatient to get crafting, but surely you can pay less than a thousand each. I buy the recipes for 10K Inf... so Cost: 20.5-34K Inf
[*]Craft them. Cost: 34.5K Influence
[*]Convert them to another random Uncommon, doesn't matter which. Cost: 1 converter (100K Inf)
[*]Convert them to within their set... 75/80% of the time, it will automatically up-convert them to Rare. Cost: 200K Inf-400K Inf depending on if it takes one or two converters to convert to a rare. If it take more, ugh you might have to eat that one.
[*]Post on the market for 500K, to ensure that you make a decent profit (Cost: 25K Posting fee)
[*]Wait. Cost: 0 Inf
[*]Pick up your winnings! Cost: Profit!!!
[*]If, for some reason, you got a crap rare enhancement that's selling on the market for like 200K or less inf or something, you'll either have to repost it for 1 inf and get what you can (call it a lost), or play roulette with converters and hope you get something good to recoup your losses.
Total Cost: 380-594K Influence
Average Sale price: 500K-2M Inf
Average profit range: -100K to 1.62M Inf, usually you make a couple hundred thousand per on average really
The law of averages works in your favor here, and you very slowly will gain the monies. You won't get super rich super fast, but you'll slowly and steadily accrue funds. If you're willing to wait and sit and see if things sell, you'll even be able to sell some of the "junk" eventually.