Trading cards and such

I've been researching everything about selling cards/turning them to gem packs, buying low and selling high.

From what I've gathered after looking at my cards it seems a lot more profitable to just sell the cards themselves, and I noticed there are huge differences in the prices depending on the local currency, so is it possible to somehow sell my cards to a different currency to make more (highly unlikely)

Steam idle master and inventory helper what do they both do and is it worth it (I don't know what else to say :/)

Blabber:

I'm tryna buy a game with steam wallet cuz I'm just surfing above a positive balance (card) every month

If you have any other questions or tips then please full send I don't really know how to communicate clearly since I've just been quiet all my life