traveler said:
Just started the game. This is my first MH. Enjoying it thus far but I've filled up my inventory rather quickly and I'm just wondering what I should sell/put in the box for later/keep as the whole item/weapon/armor-forging stuff seems quite daunting and it's hard to tell from the descriptions whether the Jaggi hide, monster fluid, etc. will be valuable enough later on to not be worth selling now.
I personally stick everything in the item box. If your hurting for money later on (you have all the mats but lack money to make what you want), you can start selling off monster parts that you don't need.
You'll learn more about the item system and what's needed to make certain things as you gain more experience with the game. You can make a more educated decision at that point. You can also check out the Monster Hunter wiki that's linked in the OP.
Saying that, it's usually standard to at least have the following (early game):
Blademaster:
Well-done steak (or Raw meat + BBQ Spit if you don't have enough), Potions, Whetstones, Paintballs, Hot/ Cold drink (depending on the environment)
Gunner:
Same as above without the Whetstones. Paintballs can be replaced with paint shots if you want. Normal Shot 2 is probably going to be your standard shot, so bring a stack +mats if you feel they won't be enough. You should bring the appropriate ammo for what you're hunting also (appropriate element for element-weak monsters, pierce shot for "long" monsters, pellet for smaller monsters, etc).
These are the standard, basic things you should bring as a new hunter. When you start getting into armor skills, things can totally change-- but at that point you should be able to better grasp these sorts of things.
Most of this is taken from my experience in MHFU, so it should hopefully apply to MH3.
(myself included)