Good answers so far, but I wanted to add a couple of things. You must remember that most auctions require the buyer to pay an additionaly 5% of the sales price. This is the commission only for the company putting the auction together. An Auction is ususally just a big warehouse of listings that are attempting to gain an acceptable offer to the several different sellers. As an agent, I have had accepted offers for REO properties, that cancelled and went to auction. The properties did not sell for what the lender (owner-REO) wanted and was later relisted. Unfortunately both buyers changed their mind, as this created a trust issue.
On my 2nd point, I really think that you should get qualified for a conventional loan if you are going to buy at the auction, as the FHA certification may be out of reach. If a home inspection is possible, I highly suggest spending the $250 to $400.
Have an agent totally follow the property and be ready, as the auction is not a sure thing and below 50% even go to escrow.