The values shown are Fair Market Values.  Once you click on an item you will be able to see the current bid amount and the next bid step.  Use Max Bid and the system will bit for you up to the Maximum amount you set.  The Max Bid must be at least two bid steps higher than the next bid step to work for you.  

Unique Items

Custom Squire Shop Lamp

Cool Collectors Item
Current Bid: $0