Following a foreclosure sale the general rule is that the amount of the debt is reduced by the net proceeds realized from the sale, setting the deficiency amount the foreclosing creditor may seek to recover.  N.C.G.S. § 45-21.31(a)(4).  However, when the foreclosing creditor is the successful high bidder at the foreclosure sale this general rule is abrogated by N.C.G.S.