There are two starting prices, one is the starting bid price that the auction house advertises, and the other is the reserve that the bank who has foreclosed on the property wants. In an auction, the bank's bottom-line dollar amount is not disclosed to the buyers. If that reserve (the bank's bottom-line) is not reached at the auction, the home does not sell.
I would have to know the address of the property and run comparables on it to know what it's market value might be. Unless I have more details, there is no way to know what the home is worth, nor what it will ultimately sell for. In an auction, there is the chance that a "bidding war" will ensue, making it even more difficult to guess.
In the end, it's about what a buyer is willing to pay. Do your homework before you go to the auction and decide in advance how high you are willing to bid. Don't let emotions get in the way, and if you're lucky, you might just score a great deal!
Good luck!! Let us know how you fared at the auction!