The Fallout 76 Atom Costs Canada guide which goes over the various pricing tiers for collecting this special currency. The atoms can be obtained within the game while playing or through a selection of microtransaction options which can get rather expensive. The various options after the first price point will offer a bonus quantity so that you can spend it on more items.
The special shop within the game will continue to grow over time so you can complete activities to work towards them or just pay with real monetary currency to gain them. The items you can buy range from apparel, to special camping items and even some decorative type things such as emotes. The full listing can be found below, note that they may go on sale or additional options be added over time. Prices are of course in Canadian if that wasn't apparent.
500 : $6.49
1000 + 100 bonus : $12.99
2000 + 400 bonus : $24.99
4000 + 1000 bonus : $49.99
You can see all of the items that can be purchased from the store at launch below or check out the general hub in order to view additional coverage. There are quest lines covered, things to purchase and of course a look at various places in the wasteland including secret locations.
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