Binding" and "NonBinding"
eBay offers sellers two choices for real estate auctions, "Binding" and "NonBinding." Don't be confused by those terms, because neither results in a legally binding contract to buy the real estate.
So how do they differ? When you bid on a Binding real estate auction, you indicate a true intent to buy, so you can receive negative eBay feedback if you win but choose not to complete the transaction. You cannot receive negative feedback if you do not complete the purchase of real estate won in a NonBinding auction.
Advertising Option
Some of the properties on online auctions are placed there as ads only. No bidding takes place. That option is a fairly inexpensive way for sellers to get extra exposure for their real estate.
The Bottom Line
Follow the links to read each auction company's rules. Policy guidelines are sometimes buried deep in the Web site, so you must dig a little to find them. eBay has a Real Estate Rules page. For others, start by reading their "help" pages, or look for words like "policies" and "rules."