Another possibility after the foreclosure sale is a deficiency judgement. When the total amount owed by the homeowner exceeds the sale price of the property, the lender can pursue a deficiency judgement in some states. In Florida, the lender can do so separately from the foreclosure action, or as a part of it. The amount granted is up to the court and it cannot be more than the difference between fair market value of the property and the judgement.
In the rare event that there is a bid in excess of the judgement amount rendered by the court, then the excess will first go to pay off any other lien holders on the house. Any remainder after these payments would then revert to the homeowner.