Refining
Ok then, refining has a chance of failing, decreasing when it becomes +3, when it become +5, it has a chance of breaking.
The stones on the left are for 31~50 weapons, there are low level ones, I just don't have any since my level is higher.
The stones on the right are unlimited stone, meaningthe level doesn't matter, it can refine any weapon of any range.
Socketing
There are several sockets, later on I'll put Darness' socket faq onto here if I get his permission.
Red gems are rare, but their stats are limited to the better stats(still a huge bundle), while green gems have a way bigger bundle, meaning red gems have a better chance of getting good stats, though it's still possible with the green gem as well, just depends on luck.
Breaking
While at low level, you will break every equipment that you don't need for alchemy purposes.
Selling
Selling mostly occurs later in the game where breaking isn't as useful anymore, since you already have the highest alchemy type clothes, of course that will change sooner or later when the new alchemist comes in.
Trashing
I don't see a reason to trash something when you can just sell it, it's ostly there when you have an item that can't be breaked or sold but you want to get rid of it.