I reference 'List price' in my Pricing Rule but what if no List price is available on Amazon for an item?

Sellery has a fall back order that is used when a value is indicated in your Pricing Rule, but for whatever reason, doesn't exist or isn't sent by Amazon through their API. 

If the List price is not available, Sellery will next look for the Lowest New Price, followed by the Lowest Used, and finally, your item's Minimum Price.