Beginners Guide TL;DR version
Just because you don’t want a game doesn’t mean you can’t capitalize on how other people value it. Some people value based solely on grey market prices and possibly h:w as well, however it may be unclear at to how many people you use it to value their games, because a minority of people included it in their overview.
Have ⇄ : Want ★ ratio is the numbers of traders who have this item available to trade in ratio to the number of traders who have it wishlisted. You can sort your wishlist tab by highest haves for games you could start getting with your easy to get games. Keep a close eye on past or recent Humble Choice and other recent bundles.
Purchase-disabled games (marked with "⎚" in your tradables or on the item page) are probably the most important thing to notice when you're starting out. They are games removed, banned, or de-listed from Steam. Here is a list of all currently known de-listed games. Some traders on here will be eager to low-ball them away from you when you're starting out in order to gain a profit by selling it on the grey market. Games such as Rocket League, F1 2011, F1 2012, Poker Night at the Inventory or Poker Night 2 are a few previously easily obtainable games that you could trade for God of War or something of more equal / more value.
What is the grey market? The grey market is any site that unofficially sells video game keys, such as 
All of these websites use reflinks, meaning that each click will earn them some money. This is done by setting a cookie on your browser that will be associated with all future purchases from the store you click on. While ITAD has this clearly indicated by the ♥ icon next to the store, gg.deals' reflinks are hidden behind multiple redirects, and are invisible even when moving your cursor over a link.
IsThereAnyDeal is a website that lists the historically lowest sale price of a video game across multiple official key sources. At the bottom of each Barter game page, there is a button that links to the corresponding ITAD page for that item ( 
The ITAD price chart tab will show you how recently the game has been on sale, as well as whether the lowest price is erroneously significantly lower than the avg. sale price.
SteamDB can show you the historical low of a game on Steam (SteamDB indexes only Steam games). Games without a sale in a long time are something to take notice of and may correspond with a higher grey market price than the historical low.
- Signs that your trading partner is looking to profit/re-sell your keys on the grey market: On the offer page you might see collection indicators such as "tradable", "wishlist (custom)"(the game isn't from their Steam wishlist, it's from their Barter wishlist), and/or "wishlist (extra)" (games is for a "friend") next to games they want from you in an offer. Another sign is a private Steam profile / 0 games in their Barter library. Checking all values will help you in all trades regardless of these signs.
- It's highly recommended NOT to trade you Humble Bundle games as gift links because they are more ideal for resellers to sell on the grey market (they can be checked to ensure that they haven't been activated yet, in a way that keys can't), and them being sold on the grey market can be tracked back to you, then possibly lead to your Humble Bundle account being deactivated(possibly taking all your keys with them, and stopping you from purchasing anymore bundles with a new account)
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Region restricted games are tagged with 🌐. You can see which regions the lock applies to by clicking on the game bundle on its Barter game page (under Notices), then the
SteamGifts link on its bundle page. Check Steamgifts to make sure a trade will work between both parties in a trade. Setting your region as specifically as possible through your Barter profile’s 🌐Region Settings is essential in avoiding any potential disputes. -
Curator Connect Copies are tagged with
on barter. These games are delivered by adding you to a curator group, promoting you to a moderator position, delivering the game directly to your account (bypassing key activation, there-by any chance of you selling it on the grey market), then de-modding you, and possibly kicking you from the group. These curator groups acquire these copies by approaching devs with the promise of review / promotion, then abuse the trust of these devs by trading them for games they can sell on the grey market. Putting in your overview that you wouldn't like to receive these offers and they should steer clear, you could additionally block these traders (there aren't many).
- "Dev" or "Dev Sourced" keys are typically obtain by traders approaching devs by email as the owner of a "reputable" Youtube channel interested in copies of a game. They can't directly sell these on the grey market, because the devs would revoke them and they would have to refund the purchase or lower their seller rating. To get around this they trade for games which can be sold on the grey market without the certainty of revocation.
- Some games may activate as "beta" or "for beta testing", but be updated in line with the full retail version and have all features available.
on barter. These games are delivered by adding you to a curator group, promoting you to a moderator position, delivering the game directly to your account (bypassing key activation, there-by any chance of you selling it on the grey market), then de-modding you, and possibly kicking you from the group. These curator groups acquire these copies by approaching devs with the promise of review / promotion, then abuse the trust of these devs by trading them for games they can sell on the grey market. Putting in your overview that you wouldn't like to receive these offers and they should steer clear, you could additionally block these traders (there aren't many).- Steam Gift games are typically more valuable than keys because the certainty that they work, and in most case you can't purchase a game directly to your inventory anymore.
- Overviews state a trader's preferred conduct, any values they use when deciding to accept an offer, or act as a general bio.
- It's recommended to leave a positive rep on your trading partner's SteamTrades profile after a successful trade.
- Some games will have a major discrepancy in h:w ratio between different game packages / editions, so a game that seems hard to trade for might be easier than you think when looking for a different package through the Barter game page's ⚯ Related tab. This is a common theme with past Humble Choice games. Control featured in March 2021 Humble Choice doesn't have all the DLC of the normal version, and isn't as updated.
- Region excluded 🚫 is a game that isn’t included when purchasing that bundle from a certain region.
Augmented Steam is a highly recommended addon available for Edge, Chrome, and Firefox. It provides ITAD sales info and additional links on each game page, filters for better browsing, highlights for owned and wishlisted game, and is full customizable through its options menu.
Enhanced Barter is a highly recommended userscript applied easily through the Tampermonkey add-on. It adds a
The Barter.vg Discord is welcome to anybody and will happily help beginners with trading advice, support, additional information for identifying bad trades and actively discuss new bundles. You can also opt-in to receive notifications about new offers or when another trader adds to their tradables an item that you follow.
The Barter.vg steam discussion group is available for any concerns with your Barter.vg experience.
Official Barter.vg Steam profile
Additional tools available for Barter.vg