Timothy Martinez, owner of Koenig & Vits, Inc. ("K&V"), guaranteed K&V’s debt to Community Bank & Trust. The guaranty stated that the bank was not required to seek payment of the debt from any other source before enforcing the guaranty; K&V defaulted. Through a Wisconsin state court, the bank sought payment of $536,739.40, plus interest, at the contract rate of 7.5 percent, from Martinez. Martinez argued that the bank could not enforce his guaranty while other funds were available to satisfy K&V’s debt. For example, the debt might be paid out of the proceeds of a sale of corporate assets. Is this an effective defense to a guaranty?