When it comes to auctions, there are many ways to describe the items that are up for bid. Instead of using the same phrase "on auction," you can use different synonyms that will spice up your writing. For example, you could use the words "up for bid," "for sale," or "on the block." You could also use the phrase "going once, going twice" to evoke the excitement of a live auction. Other synonyms include "on the market," "under the hammer," and "on sale." Using different words to describe an auction not only makes your writing more interesting, but it also provides variety for your readers.