inventory items

[LilTurk]

How do I find the address responsible to increment the item and decrement it in a way I can't lose any item I have used especially with games such as Dead Space and TheCallisto protocol.

[Paul44]

^ when you are tackling "total" values - such as ammo, money, etc - then one should be able to easily find the writing opcode; and lock consumption accordingly. However, when you're talking about complexer items - such as (composed) suits, ingredients based on some recipe of items, etc - that is an entire different thing as these "link" (unique/single) items into 1 main object.
=> in those cases, you will have to tackle the routines that manage these particular objects... (~ not my "thing" btw)
(btw: the game will show you a counter indeed, which "simply" is a counter of the number of (sub)records currently linked)

ps: it might help to mention which games you're trying to research; someone might know more on the subject then...