Ok so here's a very short basic guide on how to get your sub-stats you want, without ever spending money on those re-rolls.
Grades 1 through 8:
Note: This section includes all Dropped, Crafted, NPC, items. There are no such thing as a crafted item that you cannot enchant from a grade 1 max stat scroll. As for jewelry, only some~ of the jewelry is a unique grade. The rest can follow the process below.
-Simply purchase Max Tier stat items of your preference from someone crafting max stat items.
-Consume the item with a blank scroll and Enchant the item you like.
Uniques:
This ones a bit trickier, but the cheapest way, is the farm the low level uniques, and max grade uniques [not the epics, things like bow of talons, etc]
Consume them when you find the right one, and Enchant the item you like. These can be applies to 160 dropped jewelry, uniques, and epics.
Event Grades:
The best source for farmable max stat are the leprechaun boxes.
Simply open a tonne until you get 1/set of the stats you want, and repeat the Enchanting process.
Item Mall:
This one cost your pocket money, but is absolutely cheaper to start. If you solely use this process you may shoot yourself in the foot.
Buy or buy from someone the 1$ equipment box sets.
This will give you 4 sub-stats for essentially the price of one.
When you find the stat repeat the Enchanting process.
Note: It MAY be cheaper to purchase these boxes, open for a few max tier items, and re-roll them, however it is not a requirement or verifiable to be any better at this point.
Enchantment scrolls can be purchase from either the IM or Valor point shop under the consumable tab.
I will link a guide to farming Valor very quickly sometime soon and link it here. At a modest rate I can farm 2000-3000 Valor in a few short hours, without ever touching a dungeon.