Bidding increments help make sure that the bids for an item increase at an appropriate amount. They’re based off the current bid of the item (not the item’s overall value).
By default, if the current bid is under $200, the next bid must be at least $10 higher than the current bid. If the current bid is between $200 and $500, the next bid placed must be at least $25 greater than the current bid. And if the current bid is over $500, then the next bid must be at least $50 greater than the current bid. These increments are fully customizable though, so you can change them to follow whatever rules you like.
To change these settings, once you’re in Auctions, head to ‘Settings’, then ‘Advanced’ to change the bid increments. Below is a helpful video that will walk you through the process
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