Game contains lootboxes that are openable without paying, however this is subject to change. Items are sellable on the community market.

Game contains lootboxes that are only openable by paying real money.

Contains "loot cases" which are only openable with real money.

Contains built-in ads for cosmetic microtransactions. Uses a middleman currency. Paid version simply gives you a given amount of middleman currency with no other features.

Contains lootboxes purchaseable via microtransactions. Multiple reviewers have stated that these lootboxes are all but necessary to avoid a massive grind near the end of the game.

The grand-daddy of lootboxes and cosmetic microtransactions. Contains both in-game micotransactions via the "Mann Co Store" and "crates" that drop random items when real money is paid to unlock them.