I don’t synchronize my eBay items with my Bonanza items. So, I’m not 100% accurate about my answer. However, I don’t believe that making a price change or shipping change on your eBay items will automatically change the listing on Bonanza if you don’t re-import your items. When reimporting items from eBay, there is an option to overwrite previously imported listings.

Basically, the main function of synchronization is to update your listings when they either sell or are removed. If you change the listing details (price, description, shipping) in one location or the other, it shouldn’t change in the other location. But, if you change the TITLE of the item, then I don’t think synchronization works anymore for that item, because Bonanza may see the changed title as a different item.

As far as changing your price, you should be able to do that either through “Add or Edit Items” or by using the Batch Edit option.

“If you’re making changes to your listings on eBay after you’ve already imported them to Bonanza and want those changes to show on your Bonanza listings, then you’ll want to indicate that the importer should override existing items.”

“The ‘override existing’ option will only apply to one-off imports or the very first import of an ongoing ‘sync’.
Subsequent syncs will revert back to importing new items only.
You must edit your import settings prior to each sync to indicate the importer should revise previously imported items once changes have been made to your listings on eBay.”

https://support.bonanza.com/hc/en-us/articles/360001111052#importMultipleTimes

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[URL removed] “…with no way to edit the listing (as far as I can tell).”

You can edit Your listings as many times as You need [URL removed]

https://support.bonanza.com/hc/en-us/articles/360001137111-How-do-I-edit-an-item-

https://support.bonanza.com/hc/en-us/articles/360000605672-Using-the-Batch-Editor (check all tools/options provided in Batch editor, as You may find them very helpful).