Trading is an in-forum system that lets roleplayers exchange items with other roleplayers. Introduced by BonkUppercut, this system allows players to swap weapons, hats, misc items, tools and more with other players. Later on, Valve also added the ability to trade items from different games to each other.
Metal is often used as a trading currency by traders, and is traded for items according to their value in Metal. The value of specific items is usually given in terms of Refined Metal, or "ref" (e.g. 1.33 ref, 3 ref, etc.). To know how much metal is being asked for an item, the specific values for each type of metal are as given as: 1 Scrap = 0.11 ref, 1 Reclaimed Metal (or rec) = 0.33 ref, 1 Refined Metal = 1 ref. Since a scrap is produced from 2 weapons, a single Unique weapon is sometimes considered as equivalent to 0.05 ref. However, it is usual to see individual Unique weapons sold for a scrap each, by players trying to make profit out of trades.
For items with higher value, higher-level "currencies" are used. Keys are used as the next tier of currency, although their equivalent in Metal is often accepted as substitute when trading. Bill's Hats are sometimes used as the next level of currency due to their high value in Keys and/or metal. Earbuds, or "Buds", considered to be extremely rare and valuable, are often considered as the top tier of TF2 currency, and are used as such to buy and sell the most expensive items available.
Item Value Edit
In general, the value of items is defined by their rarity, that is, the difficulty and/or expense in acquiring them by a player. By extension, item rarity is usually tied to an item's Quality. Hence, Unique weapons, the most usual drops in the game, have the lowest value of all items, due to them being the most usual drops, as well as being craftable. Mann Co. Supply Crates are also common drops and as such also considered of low value. Vintage items are considered more expensive, due to their originally higher crafting value, and their general unavailability at present. Strange items have a higher value than Uniques since they can only be obtained from Supply Crates, but their price varies wildly depending on each item's specific probability of being obtained from a Crate, as well as the availability of the crate they can be obtained from. Genuine item values are often higher than the aforementioned, due to the related expense of obtaining them as promotional items, and the limited timeframe to obtain them this way.
Haunted items are also considered to have a higher value, due to their dropping window being limited to Halloween events and maps. Festive weapons have a similar seasonal limitation, but are considered to be of a much higher value, due to the strict timeframe allowed for obtaining them from special Christmas Event crates (the crates themselves being destroyed after the end of the event), their relative probability of being obtained from crates, and their cosmetic decorations. Festive weapons of a Strange quality have an even higher value due to their even lower probability of being obtained.
Items of any quality are considered to be "dirty" when they contain additional descriptive text ("gifted by ___", craft #, etc.), or when they have certain trading limitations, such as needing gift-wrap, or being uncraftable. Dirty items are considered to be of lesser value than "clean" items devoid of any of these attributes.
Items with attributes added by Tools such as color from Paint Cans or Strange Parts, usually have the value of such items added to the total value of the item up for trade.
Unusual Items Edit
Unusual items are considered to be the most valuable and expensive items for trade in the game by a wide margin. As such, they are considered to be in their own separate tier of high prices (usually given in terms of Earbuds or in keys to a lesser extent). In addition to the visual appeal of the Particle effectsthese items sport, their 1% probability of being acquired from Crates makes them extremely hard to come by, and makes their base trading price extremely high. However, within its own realm of Unusual prices, the value of an Unusual item may vary wildly according to visual or thematic appeal, rarity, and general desirability.