Valve probably doesn’t want you to use Steam as a bank and stash your money there – at least you’ll get a lock if you overdo it.
What is the lock about? Valve restricts how much money each user can add to their Steam balance per day. If you exceed this limit, Valve will lock the function for you to add new money to your balance.
For US customers, this limit is $2,000. In other currencies, the limit is supposed to be at a value that roughly corresponds to $2,000. (via Steam).
If you want to buy games worth €3,000 on Steam in one day with Steam credit, this limit will get in your way in between.
Can you bypass the limit? No, probably not, as the situation of Twitch streamer Jynxzi shows. The content creator had Steam gift cards sent to him but then received a 3-day marketplace restriction. Instead of being unable to add money until the end of the day, he could then not be active on the Steam marketplace for 3 days.
Steam warns you, however, if there is a risk of a marketplace restriction due to the acceptance of a gift card.
Furthermore, Steam prohibits selling items like skins in Counter-Strike 2 on the community market if the seller’s Steam balance together with the sale price of the item would exceed $2,000.
If you have spent thousands of euros on Steam, you shouldn’t hope that you can easily pass on the account to your loved ones in the event of death: A user actually inquired at Steam and received a disappointing answer: A user asks Valve if he can inherit his many games on Steam – They respond
